fix the following 'make includecheck' warning:

  drivers/scsi/ibmvscsi/ibmvscsi.c: asm/firmware.h is included more than once.
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
LKML-Reference: <1247067016.4382.78.camel@ht.satnam>
Acked-by: Brian King <brking@linux.vnet.ibm.com>