MCAsmParser: relax declaration parsing

The Linux kernel defines empty macros for compatibility with ARM UAL syntax.
The comma after the name is optional, and if present can be safely lexed.  This
improves compatibility with the GNU assembler.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201474 91177308-0d34-0410-b5e6-96231b3b80d8
Fix broken CHECK lines

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201479 91177308-0d34-0410-b5e6-96231b3b80d8
Add a DIELoc class to cover the DW_FORM_exprloc set of expressions
alongside DIEBlock and replace uses accordingly. Use DW_FORM_exprloc
in DWARF4 and later code. Update testcases.

Adding a DIELoc instead of using extra forms inside DIEBlock so
that we can keep location expressions separate from other uses. No
direct use at the moment, however, it's not a lot of code and
using a separately named class keeps it somewhat more obvious
what's going on in various locations.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201481 91177308-0d34-0410-b5e6-96231b3b80d8