video_core: Remove #pragma warning directives for external headers

src/video_core/command_classes/codecs/codec.h

@@ -14,18 +14,10 @@ extern "C" {
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wconversion"
 #endif
-#ifdef _MSC_VER
-#pragma warning(push)
-#pragma warning(disable : 4242) // conversion from 'type' to 'type', possible loss of data
-#pragma warning(disable : 4244) // conversion from 'type' to 'type', possible loss of data
-#endif
 #include <libavcodec/avcodec.h>
 #if defined(__GNUC__) || defined(__clang__)
 #pragma GCC diagnostic pop
 #endif
-#ifdef _MSC_VER
-#pragma warning(pop)
-#endif
 }
 
 namespace Tegra {

src/video_core/command_classes/vic.cpp

@@ -9,17 +9,10 @@ extern "C" {
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wconversion"
 #endif
-#ifdef _MSC_VER
-#pragma warning(disable : 4244) // conversion from 'type' to 'type', possible loss of data
-#pragma warning(push)
-#endif
 #include <libswscale/swscale.h>
 #if defined(__GNUC__) || defined(__clang__)
 #pragma GCC diagnostic pop
 #endif
-#ifdef _MSC_VER
-#pragma warning(pop)
-#endif
 }
 
 #include "common/assert.h"