ppc: Properly tag the translation cache based on MMU mode

ppc: Properly tag the translation cache based on MMU mode

We used to always flush the TLB when changing relocation mode in
MSR:IR and MSR:DR (ie. MMU on/off for Instructions and Data).

We don't anymore since we have split mmu_idx for instruction and data.

However, since we hard code the mmu_idx in the translated code, we
now need to also make sure MSR:IR and MSR:DR are part of the hflags
used to tag translated code, so that we use different translated
code for different MMU settings.

Darwin gets hurt by this problem.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>