arm64: head.S: get rid of x25 and x26 with 'global' scope

Currently, x25 and x26 hold the physical addresses of idmap_pg_dir
and swapper_pg_dir, respectively, when running early boot code. But
having registers with 'global' scope in files that contain different
sections with different lifetimes, and that are called by different
CPUs at different times is a bit messy, especially since stashing the
values does not buy us anything in terms of code size or clarity.

So simply replace each reference to x25 or x26 with an adrp instruction
referring to idmap_pg_dir or swapper_pg_dir directly.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>

arch/arm64/kernel/sleep.S

@@ -102,8 +102,6 @@ ENTRY(cpu_resume)
 	/* enable the MMU early - so we can access sleep_save_stash by va */
 	adr_l	lr, __enable_mmu	/* __cpu_setup will return here */
 	adr_l	x27, _resume_switched	/* __enable_mmu will branch here */
-	adrp	x25, idmap_pg_dir
-	adrp	x26, swapper_pg_dir
 	b	__cpu_setup
 ENDPROC(cpu_resume)