Blackfin: Add missing __user annotations to put_user

typeof() will not inherit the __user annotation so we have to explicitly
specify this for '_p'.

This fixes the following and quite a few similar warnings from spatch:

	kernel/sys.c:884:26: warning: incorrect type in initializer (different address spaces)
	kernel/sys.c:884:26:    expected unsigned int *_p
	kernel/sys.c:884:26:    got unsigned int [noderef] [usertype] <asn:1>*ruidp
	kernel/sys.c:885:26: warning: incorrect type in initializer (different address spaces)
	kernel/sys.c:885:26:    expected unsigned int *_p
	kernel/sys.c:885:26:    got unsigned int [noderef] [usertype] <asn:1>*euidp
	kernel/sys.c:886:26: warning: incorrect type in initializer (different address spaces)
	kernel/sys.c:886:26:    expected unsigned int *_p
	kernel/sys.c:886:26:    got unsigned int [noderef] [usertype] <asn:1>*suidp

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Bob Liu <lliubbo@gmail.com>