Harden/relax clang/test/CodeGen/opt-record-MIR.c test

[lebedev.ri]

Summary

If the build path is short, Line field can end up fitting on the same line as File,
but the {{.*}} would consume it. Keeping in mind rL293149, i think we can fix it,
while keeping it working when there are and there are not any quotations.
At least this fixes this test for me.

[lebedev.ri]

Simplify regex even more.

[anemet]

LGTM, thanks!

[lebedev.ri]

In D49348#1164579, @anemet wrote:

LGTM, thanks!

Thank you for the review.
(I'll watch the bots, obviously)

test/CodeGen/opt-record-MIR.c

 }
 
 // REMARK: opt-record-MIR.c:10:11: remark: {{.}} spills {{.}} reloads generated in loop
 // NO_REMARK-NOT: remark:
 
 // YAML: --- !Missed
 // YAML: Pass:            regalloc
 // YAML: Name:            LoopSpillReload
-// YAML: DebugLoc:        { File: {{.*}},
-// YAML:                    Line: 10, Column: 11 }
+// YAML: DebugLoc:        { File: {{.*}}.c{{['"]*}},
+// YAML:                    Line: 10,
+// YAML:                    Column: 11 }
 // YAML: Function:        foo
 // YAML: Args:
 // YAML:   - NumSpills:       '{{.}}'
 // YAML:   - String:          ' spills '
 // YAML:   - NumReloads:      '{{.}}'
 // YAML:   - String:          ' reloads '
 // YAML:   - String:          generated
 // YAML: ...