[StrTable] Fix modules build and clean up stale files (llvm#125979)

I missed a few places to tidy up from before using the tablengen files
directly for the builtins. I didn't remove all of the modulemap entries
and there were two small `.def` files left lingering. This should clean
all of that up. I went through to cross check the list of files and it
looks correct now.

Author: chandlerc

clang/include/clang/Basic/BuiltinsSME.def

@@ -49,11 +49,7 @@ module Clang_Basic {
   textual header "clang/Basic/BuiltinsLoongArchLASX.def"
   textual header "clang/Basic/BuiltinsLoongArchLSX.def"
   textual header "clang/Basic/BuiltinsMips.def"
-  textual header "clang/Basic/BuiltinsNEON.def"
   textual header "clang/Basic/BuiltinsPPC.def"
-  textual header "clang/Basic/BuiltinsRISCVVector.def"
-  textual header "clang/Basic/BuiltinsSME.def"
-  textual header "clang/Basic/BuiltinsSVE.def"
   textual header "clang/Basic/BuiltinsSystemZ.def"
   textual header "clang/Basic/BuiltinsVE.def"
   textual header "clang/Basic/BuiltinsVEVL.gen.def"