[AMDGPU] Set metadata access for explicit section
Summary:
This patch provides a means to set Metadata section kind
for a global variable, if its explicit section name is
prefixed with ".AMDGPU.metadata."
This could be useful to make the global variable go to
an ELF section without any section flags set.
Reviewers: dstuttard, tpr, kzhuravl, nhaehnle, t-tye
Reviewed By: dstuttard, kzhuravl
Subscribers: llvm-commits, arsenm, jvesely, wdng, yaxunl, t-tye
Differential Revision: https://reviews.llvm.org/D55267
llvm-svn: 348922