arm64: make label allocation style consistent in tishift

This is entirely cosmetic, but somehow it was missed when sending
differing versions of this patch. This just makes the file a bit more
uniform.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Danny Lin <danny@kdrag0n.dev>
Change-Id: Icbae2ec2ba15e696a9d0c63c9ce369f217c023da