ARM: 7950/1: mm: Fix stage-2 device memory attributes

The stage-2 memory attributes are distinct from the Hyp memory
attributes and the Stage-1 memory attributes.  We were using the stage-1
memory attributes for stage-2 mappings causing device mappings to be
mapped as normal memory.  Add the S2 equivalent defines for memory
attributes and fix the comments explaining the defines while at it.

Add a prot_pte_s2 field to the mem_type struct and fill out the field
for device mappings accordingly.

Cc: <stable@vger.kernel.org>	[3.9+]
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mm/mm.h

@@ -38,6 +38,7 @@ static inline pmd_t *pmd_off_k(unsigned long virt)
 
 struct mem_type {
 	pteval_t prot_pte;
+	pteval_t prot_pte_s2;
 	pmdval_t prot_l1;
 	pmdval_t prot_sect;
 	unsigned int domain;