Fix dev_load_map()

[andyhhp]

Clang complains:

dev.c:74:2: warning: variable 'dev_map' is uninitialized when used here [-Wuninitialized] dev_map &= !DEV_MAP_V0_MASK; ^~~ 1 warning generated.

On closer inspection, there are several other serious errors:

• 'x &= !mask' makes no sense, and looks as if someone confused bitwise and logcal not operators. Judging the uses of &= without a not operator, they appears to be confused with |= as well.

• dev_map, if it isn't elided fully by the compiler due to UB, will contain 1 bit of stack rubble, and zeros elsewhere. As the valid bit for UINT0 is clear, the one bit of stack rubble doesn't alter hardware behaviour.

• dev_base_low is set to 0, then has various things including dev_bitmap_paddr, and-ed out. This means that hardware is loaded with 0 and doesn't point at DEV in the first place.

Rewrite the function entirely, using the comments as guidance.

Signed-off-by: Andrew Cooper andrew.cooper3@citrix.com

[dpsmith]

I have RB and TB this PR. Please update commit signoff and will be merged.