fix spelling mistakes

SPIRV/SPVRemapper.cpp

@@ -573,7 +573,7 @@ namespace spv {
             op_fn_nop);
 
         // Window size for context-sensitive canonicalization values
-        // Emperical best size from a single data set.  TODO: Would be a good tunable.
+        // Empirical best size from a single data set.  TODO: Would be a good tunable.
         // We essentially perform a little convolution around each instruction,
         // to capture the flavor of nearby code, to hopefully match to similar
         // code in other modules.

SPIRV/SpvBuilder.cpp

@@ -2319,7 +2319,7 @@ void Builder::simplifyAccessChainSwizzle()
 
 // To the extent any swizzling can become part of the chain
 // of accesses instead of a post operation, make it so.
-// If 'dynamic' is true, include transfering a non-static component index,
+// If 'dynamic' is true, include transferring a non-static component index,
 // otherwise, only transfer static indexes.
 //
 // Also, Boolean vectors are likely to be special.  While