staging/keucr: eliminate sparse warnings in ms.c

Eliminate sparse warnings in ms.c:

drivers/staging/keucr/ms.c:28:58: warning: right shift by bigger than source value
drivers/staging/keucr/ms.c:31:58: warning: right shift by bigger than source value
drivers/staging/keucr/ms.c:789:59: warning: cast truncates bits from constant value (ffffff7f becomes 7f)

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>