gl_shader_disk_cache: Make hash specializations noexcept

The standard library expects hash specializations that don't throw
exceptions. Make this explicit in the type to allow selection of better
code paths if possible in implementations.

src/video_core/renderer_opengl/gl_shader_disk_cache.h

@@ -70,14 +70,14 @@ namespace std {
 
 template <>
 struct hash<OpenGL::BaseBindings> {
-    std::size_t operator()(const OpenGL::BaseBindings& bindings) const {
+    std::size_t operator()(const OpenGL::BaseBindings& bindings) const noexcept {
         return bindings.cbuf | bindings.gmem << 8 | bindings.sampler << 16;
     }
 };
 
 template <>
 struct hash<OpenGL::ShaderDiskCacheUsage> {
-    std::size_t operator()(const OpenGL::ShaderDiskCacheUsage& usage) const {
+    std::size_t operator()(const OpenGL::ShaderDiskCacheUsage& usage) const noexcept {
         return static_cast<std::size_t>(usage.unique_identifier) ^
                std::hash<OpenGL::BaseBindings>()(usage.bindings) ^ usage.primitive << 16;
     }