[spirv-reader] Remove orphaned TODOs

TODOs in the test file are or were in the function_arithmetic_test.cc

Change-Id: I679dbf0019e12e26488ccc310dfb03a535628e0b
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/23462
Reviewed-by: dan sinclair <dsinclair@google.com>
diff --git a/src/reader/spirv/function.cc b/src/reader/spirv/function.cc
index 260fd69..9d3d526 100644
--- a/src/reader/spirv/function.cc
+++ b/src/reader/spirv/function.cc
@@ -2206,7 +2206,6 @@
     default:
       break;
   }
-  // TODO(dneto): emit fallthrough
   return success();
 }
 
diff --git a/src/reader/spirv/function_bit_test.cc b/src/reader/spirv/function_bit_test.cc
index 549be19..01a7b98 100644
--- a/src/reader/spirv/function_bit_test.cc
+++ b/src/reader/spirv/function_bit_test.cc
@@ -621,24 +621,6 @@
 // TODO(dneto): OpBitReverse
 // TODO(dneto): OpBitCount
 
-// TODO(dneto): OpSRem. Missing from WGSL
-// https://github.com/gpuweb/gpuweb/issues/702
-
-// TODO(dneto): OpFRem. Missing from WGSL
-// https://github.com/gpuweb/gpuweb/issues/702
-
-// TODO(dneto): OpVectorTimesScalar
-// TODO(dneto): OpMatrixTimesScalar
-// TODO(dneto): OpVectorTimesMatrix
-// TODO(dneto): OpMatrixTimesVector
-// TODO(dneto): OpMatrixTimesMatrix
-// TODO(dneto): OpOuterProduct
-// TODO(dneto): OpDot
-// TODO(dneto): OpIAddCarry
-// TODO(dneto): OpISubBorrow
-// TODO(dneto): OpIMulExtended
-// TODO(dneto): OpSMulExtended
-
 }  // namespace
 }  // namespace spirv
 }  // namespace reader