Set `BOOTLOADER = stm32-dfu` for all applicable STM32 boards (#12956)

* Set bootloader to stm32-dfu for STM32F303

* Set bootloader to stm32-dfu for STM32F0x2

* Set bootloader to stm32-dfu for STM32F4x1

* Set bootloader to stm32duino for sowbug

* Delete redundant bootloader_defs headers

* Add some missing MCU name comments

* Move APM32 dfu-suffix overrides underneath bootloader

* Remove redundant STM32_BOOTLOADER_ADDRESS defines/rules

8 files changed, 26 insertions, 2 deletions

diff --git a/keyboards/mechlovin/adelais/rules.mk b/keyboards/mechlovin/adelais/rules.mk
index da4ad3e57c..73e90befbe 100644
--- a/keyboards/mechlovin/adelais/rules.mk
+++ b/keyboards/mechlovin/adelais/rules.mk
@@ -2,6 +2,8 @@
 MCU = STM32F303
 BOARD = QMK_PROTON_C
 
+# Bootloader selection
+BOOTLOADER = stm32-dfu
 
 # Build Options
 #   change yes to no to disable
diff --git a/keyboards/mechlovin/hannah60rgb/rules.mk b/keyboards/mechlovin/hannah60rgb/rules.mk
index 2fe4bb7aa5..3d11b3c9ab 100644
--- a/keyboards/mechlovin/hannah60rgb/rules.mk
+++ b/keyboards/mechlovin/hannah60rgb/rules.mk
@@ -2,6 +2,9 @@
 MCU = STM32F303
 BOARD = QMK_PROTON_C
 
+# Bootloader selection
+BOOTLOADER = stm32-dfu
+
 # Build Options
 #   change yes to no to disable
 #
diff --git a/keyboards/mechlovin/hannah65/rules.mk b/keyboards/mechlovin/hannah65/rules.mk
index 57ead17faa..656722353c 100644
--- a/keyboards/mechlovin/hannah65/rules.mk
+++ b/keyboards/mechlovin/hannah65/rules.mk
@@ -2,6 +2,9 @@
 MCU = STM32F303
 BOARD = QMK_PROTON_C
 
+# Bootloader selection
+BOOTLOADER = stm32-dfu
+
 # Build Options
 #   change yes to no to disable
 #
@@ -19,4 +22,4 @@ RGBLIGHT_ENABLE = no        # Enable keyboard RGB underglow
 BLUETOOTH_ENABLE = no       # Enable Bluetooth
 AUDIO_ENABLE = no           # Audio output
 
-DEFAULT_FOLDER = mechlovin/hannah65/rev1
\ No newline at end of file
+DEFAULT_FOLDER = mechlovin/hannah65/rev1
diff --git a/keyboards/mechlovin/hex6c/rules.mk b/keyboards/mechlovin/hex6c/rules.mk
index 99aa532c26..0af4a07f70 100644
--- a/keyboards/mechlovin/hex6c/rules.mk
+++ b/keyboards/mechlovin/hex6c/rules.mk
@@ -1,8 +1,10 @@
 # MCU name
 MCU = STM32F303
-
 BOARD = QMK_PROTON_C
 
+# Bootloader selection
+BOOTLOADER = stm32-dfu
+
 # Build Options
 #   change yes to no to disable
 #
diff --git a/keyboards/mechlovin/infinity87/rev1/rules.mk b/keyboards/mechlovin/infinity87/rev1/rules.mk
index 19be0ad838..82b0f2e482 100644
--- a/keyboards/mechlovin/infinity87/rev1/rules.mk
+++ b/keyboards/mechlovin/infinity87/rev1/rules.mk
@@ -1,6 +1,10 @@
+# MCU name
 MCU = STM32F303
 BOARD = QMK_PROTON_C
 
+# Bootloader selection
+BOOTLOADER = stm32-dfu
+
 BACKLIGHT_ENABLE  = yes     # Enable keyboard backlight functionality
 
 DEFAULT_FOLDER = mechlovin/infinity87/rev1/standard
diff --git a/keyboards/mechlovin/infinity87/rgb_rev1/rules.mk b/keyboards/mechlovin/infinity87/rgb_rev1/rules.mk
index aa7adc8954..27de40424a 100644
--- a/keyboards/mechlovin/infinity87/rgb_rev1/rules.mk
+++ b/keyboards/mechlovin/infinity87/rgb_rev1/rules.mk
@@ -1,5 +1,9 @@
+# MCU name
 MCU = STM32F303
 BOARD = QMK_PROTON_C
 
+# Bootloader selection
+BOOTLOADER = stm32-dfu
+
 RGB_MATRIX_ENABLE = yes        # Use RGB matrix
 RGB_MATRIX_DRIVER = IS31FL3741
diff --git a/keyboards/mechlovin/infinity88/rules.mk b/keyboards/mechlovin/infinity88/rules.mk
index 40e4543e89..85c01d52bf 100644
--- a/keyboards/mechlovin/infinity88/rules.mk
+++ b/keyboards/mechlovin/infinity88/rules.mk
@@ -2,6 +2,9 @@
 MCU = STM32F303
 BOARD = QMK_PROTON_C
 
+# Bootloader selection
+BOOTLOADER = stm32-dfu
+
 # Build Options
 #   change yes to no to disable
 #
diff --git a/keyboards/mechlovin/tmkl/rules.mk b/keyboards/mechlovin/tmkl/rules.mk
index bbe320ff51..54a646d274 100644
--- a/keyboards/mechlovin/tmkl/rules.mk
+++ b/keyboards/mechlovin/tmkl/rules.mk
@@ -2,6 +2,9 @@
 MCU = STM32F303
 BOARD = QMK_PROTON_C
 
+# Bootloader selection
+BOOTLOADER = stm32-dfu
+
 # Build Options
 #   change yes to no to disable
 #