CRIS: macro whitespace fixes in uaccess.h

While working on arch/cris/include/asm/uaccess.h, I noticed
that some macros within this header are made harder to read because they
violate a coding style rule: space is missing after comma.

Fix it up.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>