Reland "[Driver] Default CLANG_DEFAULT_PIE_ON_LINUX to ON""

(The upgrade of the ppc64le bot and D121257 have fixed compiler-rt failures. Tested by nemanjai.)

Default the option introduced in D113372 to ON to match all(?) major Linux
distros. This matches GCC and improves consistency with Android and linux-musl
which always default to PIE.
Note: CLANG_DEFAULT_PIE_ON_LINUX may be removed in the future.

Differential Revision: https://reviews.llvm.org/D120305