re-added code in pr 1438 to fix compile with h7 with 1 usb otg

Author: hathach

src/portable/synopsys/dwc2/dwc2_stm32.h

@@ -64,6 +64,10 @@
 
   // NOTE: H7 with only 1 USB port: H72x / H73x / H7Ax / H7Bx
   // USB_OTG_FS_PERIPH_BASE and OTG_FS_IRQn not defined
+  #if (! defined USB2_OTG_FS)
+    #define USB_OTG_FS_PERIPH_BASE  USB1_OTG_HS_PERIPH_BASE
+    #define OTG_FS_IRQn             OTG_HS_IRQn
+  #endif
 
 #elif CFG_TUSB_MCU == OPT_MCU_STM32F7
   #include "stm32f7xx.h"