Fix some comment typos.

llvm-svn: 244402
diff --git a/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp b/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp
index f43fb23..5b8db3d 100644
--- a/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp
@@ -72,9 +72,9 @@
 //
 // For most functions, some of the frame areas are empty. For those functions,
 // it may not be necessary to set up fp or bp:
-// * A base pointer is definitly needed when there are both VLAs and local
+// * A base pointer is definitely needed when there are both VLAs and local
 //   variables with more-than-default alignment requirements.
-// * A frame pointer is definitly needed when there are local variables with
+// * A frame pointer is definitely needed when there are local variables with
 //   more-than-default alignment requirements.
 //
 // In some cases when a base pointer is not strictly needed, it is generated