Fix build for rtic-usb-cdc-echo example

Author: no111u3

Cargo.toml

@@ -476,7 +476,7 @@ required-features = ["stm32f411", "rtic"] # stm32f411
 
 [[example]]
 name = "rtic-usb-cdc-echo"
-required-features = ["stm32f411", "rtic"] # stm32f411
+required-features = ["stm32f411", "rtic", "otg-fs", "usb_fs"] # stm32f411
 
 [[example]]
 name = "sd"

memory.x

@@ -1,7 +1,7 @@
 MEMORY
 {
   /* NOTE K = KiBi = 1024 bytes */
-  FLASH : ORIGIN = 0x08000000, LENGTH = 64K 
+  FLASH : ORIGIN = 0x08000000, LENGTH = 128K 
   RAM : ORIGIN = 0x20000000, LENGTH = 32K
 }