Remove clang indirection, affects command line ordering

Move the last clang-specific list into the common global list.  This
affects the command line flag ordering due to the the -fdebug-prefix-map=
flag that is added by an init() function, which will force every native
rule to recompile.

Bug: 68947919
Test: m checkbuild
Change-Id: Ic2509e61e9555e9483b92a18d7e8d9913b7125cc