Revert "Revert "Utils: Remove old compiler support code""

Thomas provided a smaller fix.
This reverts commit 78fb7f44bf.

Change-Id: I1edff6477526fe4ce29df38852f47fe49117561e
Reviewed-by: Alessandro Portale <alessandro.portale@qt.io>

src/libs/utils/smallstringiterator.h

@@ -28,11 +28,6 @@
 #include <cstddef>
 #include <iterator>
 
-#pragma push_macro("noexcept")
-#ifndef __cpp_noexcept
-#define noexcept
-#endif
-
 namespace Utils {
 
 namespace Internal {
@@ -151,5 +146,3 @@ private:
 } // namespace Internal
 
 } // namespace Utils
-
-#pragma pop_macro("noexcept")