Attempt to unbreak msan bot.

r275301 made .got section be aligned on Target->GotEntrySize,
so GotEntrySize must have been initialized. We didn't initialize
it for AMDGPU.

llvm-svn: 275373
diff --git a/lld/ELF/Target.cpp b/lld/ELF/Target.cpp
index 6908d8f..437a500 100644
--- a/lld/ELF/Target.cpp
+++ b/lld/ELF/Target.cpp
@@ -1454,7 +1454,10 @@
   llvm_unreachable("invalid relocation for TLS IE to LE relaxation");
 }
 
-AMDGPUTargetInfo::AMDGPUTargetInfo() { GotRel = R_AMDGPU_ABS64; }
+AMDGPUTargetInfo::AMDGPUTargetInfo() {
+  GotRel = R_AMDGPU_ABS64;
+  GotEntrySize = 8;
+}
 
 void AMDGPUTargetInfo::relocateOne(uint8_t *Loc, uint32_t Type,
                                    uint64_t Val) const {