sparc32: fix rtrap.S typo

Fix compile problem in rtrap.S

arch/sparc/kernel/built-in.o: In function `ret_trap_userwins_ok':
arch/sparc/kernel/rtrap.S:(.text+0x1900): undefined reference to 
`PSR_SYCALL'

Signed-off-by: Robert Reif <reif@earthlink.net>
Signed-off-by: David S. Miller <davem@davemloft.net>