MIPS SIMD Architecture vector loads and stores require misalignment support.
MSA Memory access should work as an atomic operation. Therefore, it has to
check validity of all addresses for a vector store access if it is spanning
into two pages.

Separating helper functions for each data format as format is known in
translation.
To use mmu_idx from cpu_mmu_index() instead of calculating it from hflag.
Removing save_cpu_state() call in translation because it is able to use
cpu_restore_state() on fault as GETRA() is passed.
Signed-off-by: NYongbok Kim <yongbok.kim@imgtec.com>
Reviewed-by: NLeon Alrae <leon.alrae@imgtec.com>
[leon.alrae@imgtec.com: remove unused do_* functions]
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>