Simplify MipsReginfoInputSection.

MipsReginfoInputSection is basically just a container of Elf_Mips_Reginfo
struct. This patch makes that struct directly accessible from others.

llvm-svn: 256984
diff --git a/lld/ELF/InputFiles.cpp b/lld/ELF/InputFiles.cpp
index 406db8e..6a908d4 100644
--- a/lld/ELF/InputFiles.cpp
+++ b/lld/ELF/InputFiles.cpp
@@ -92,7 +92,9 @@
 }
 
 template <class ELFT> uint32_t ObjectFile<ELFT>::getMipsGp0() const {
-  return MipsReginfo ? MipsReginfo->getGp0() : 0;
+  if (MipsReginfo)
+    return MipsReginfo->Reginfo->ri_gp_value;
+  return 0;
 }
 
 template <class ELFT>