Add MMU to Armv7-A examples#120
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robamu
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Enabling the MMU means the processor can execute unaligned loads. Without an MMU all memory is strongly-ordered, for which unaligned loads are UNDEFINED. Does not apply to non-VMSA targets like Armv7-R.
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Adds MMU support to the versatileab examples run with the
armv7a-none-eabi*andthumbv7a-none-eabi*targets.This means the examples now work when those targets are modified to remove the
+strict-alignfeature. This is because enabling the MMU stops RAM being strongly-ordered, and unaligned-loads on strongly-ordered memory is UNDEFINED by the architecture. So basically, running Armv7-A without the MMU enabled is bad, and now we show how to enable the MMU.Also meant adding support for the DACR and TTBR0 registers.