arm64: Do not initialise the fixmap page tables in head.S

The early_ioremap_init() function already handles fixmap pte
initialisation, so upgrade this to cover all of pud/pmd/pte and remove
one page from swapper_pg_dir.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Jungseok Lee <jungseoklee85@gmail.com>

diff --cc arch/arm64/include/asm/page.h
Simple merge

diff --cc arch/arm64/kernel/head.S
Simple merge

diff --cc arch/arm64/mm/ioremap.c
Simple merge