common/: Remove lingering references to CFG_CMD_* symbols.

Fixed some broken instances of "#ifdef CMD_CFG_IDE" too.
Those always evaluated TRUE, and thus were always compiled
even when IDE really wasn't defined/wanted.

Signed-off-by: Jon Loeliger <jdl@freescale.com>
diff --git a/common/usb_storage.c b/common/usb_storage.c
index 2721589..0f79f36 100644
--- a/common/usb_storage.c
+++ b/common/usb_storage.c
@@ -1249,4 +1249,4 @@
 }
 
 #endif /* CONFIG_USB_STORAGE */
-#endif /* CFG_CMD_USB */
+#endif