[Driver] -static-pie: add -z text
This matches gcc -static-pie. The intention is to prevent dynamic
relocations in read-only segments.
In ld.bfd and gold, -z notext is the default. If text relocations are needed:
- -z notext: allow and emit DF_TEXTREL. DF_TEXTREL is not emitted if there is no text relocation.
- -z text: error
In lld, -z text is the default (this change is a no-op).
- -z text: error on text relocations
- -z notext: allow text relocations, and emit DF_TEXTREL no matter whether text relocations exist.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D62606