NPTL/ARC: fix __lll_lock_wait_private redefinition for static links
Commit 2d9740a65a "uclibc: nptl: fix __lll_lock_wait_private multiple definition"
did a sweeping change which did for all in tree arches at that time (ARC
wasn't)
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>