MIPS32: Mark kQuickPow as direct entrypoint

This fixes mips32 build.
This is a follow-up to Iaa31f70acabbd57c163cfeafe02eed67c1348861.

Test: successful mips32 build
Change-Id: I959304745e7f93a64fdee792c0f3199cee2eefff
1 file changed