Now that we have removed the out-of-line ll/sc atomics we can give
the compiler the freedom to choose its own register allocation.
Remove the hard-coded use of x30.
Change-Id: Ib4c41e032aa66b8a200c3fa832fe62a999c035c4
Signed-off-by: Andrew Murray <andrew.murray@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>