drivers: usb: fsl: Move USB Errata checking code

Move USB Errata checking code from "arch/powerpc" to architecture independent
file "fsl_usb.h" so that errata(s) become independent of the architecture.
For each erratum checking function for PPC arch, define a nop function for
non PPC arch for successful compilation in either case

Signed-off-by: Nikhil Badola <nikhil.badola@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>
diff --git a/drivers/usb/host/ehci-fsl.c b/drivers/usb/host/ehci-fsl.c
index 45062e6..d5361d7 100644
--- a/drivers/usb/host/ehci-fsl.c
+++ b/drivers/usb/host/ehci-fsl.c
@@ -14,7 +14,7 @@
 #include <asm/io.h>
 #include <usb/ehci-fsl.h>
 #include <hwconfig.h>
-#include <asm/fsl_errata.h>
+#include <fsl_usb.h>
 
 #include "ehci.h"