stm32fsdev: set dcd_connect API definitions to strong, Modify documentation.

src/device/dcd.h

@@ -107,8 +107,8 @@ void dcd_set_config (uint8_t rhport, uint8_t config_num);
 void dcd_remote_wakeup(uint8_t rhport);
 
 // Connect or disconnect D+/D- line pull-up resistor.
-// Defined as weak in dcd source if MCU has internal pull-up.
-// Can be strongly defined in BSP.
+// Defined in dcd source if MCU has internal pull-up.
+// Otherwise, may be defined in BSP.
 void dcd_connect(uint8_t rhport) TU_ATTR_WEAK;
 void dcd_disconnect(uint8_t rhport) TU_ATTR_WEAK;
 

src/portable/st/stm32_fsdev/dcd_stm32_fsdev.c

@@ -243,17 +243,17 @@ void dcd_init (uint8_t rhport)
   // Data-line pull-up is left disconnected.
 }
 
-// Define only on MCU with internal pull-up so BSP can override (needed on MCU without internal pull-up)
+// Define only on MCU with internal pull-up. BSP can define on MCU without internal PU.
 #if defined(USB_BCDR_DPPU)
 
-TU_ATTR_WEAK
+// Disable internal D+ PU
 void dcd_disconnect(uint8_t rhport)
 {
   (void) rhport;
   USB->BCDR &= ~(USB_BCDR_DPPU);
 }
 
-TU_ATTR_WEAK
+// Enable internal D+ PU
 void dcd_connect(uint8_t rhport)
 {
   (void) rhport;