libopenh264enc: Remove a workaround for silencing warnings about unused variables in the OpenH264 header

The 1.3 release branch of OpenH264 (as well as the master branch)
have been updated so that GCC no longer warns about this variable
as being unused.

Signed-off-by: Martin Storsjö <martin@martin.st>

libavcodec/libopenh264enc.c

@@ -70,7 +70,6 @@ static av_cold int svc_encode_init(AVCodecContext *avctx)
     SEncParamExt param = { 0 };
     int err = AVERROR_UNKNOWN;
     av_unused OpenH264Version libver;
-    (void)g_strCodecVer; // Avoid warnings due to unused static members from codec_ver.h
 
     // Mingw GCC < 4.7 on x86_32 uses an incorrect/buggy ABI for the WelsGetCodecVersion
     // function (for functions returning larger structs), thus skip the check in those