fix shaderrc generate wrong shader of matal
fix shaderrc generate wrong shader of matal

MikePopoloski/bgfx,bkaradzic/bgfx,jpcy/bgfx,fluffyfreak/bgfx,jdryg/bgfx,attilaz/bgfx,LWJGL-CI/bgfx,LWJGL-CI/bgfx,fluffyfreak/bgfx,attilaz/bgfx,fluffyfreak/bgfx,fluffyfreak/bgfx,bkaradzic/bgfx,MikePopoloski/bgfx,jpcy/bgfx,LWJGL-CI/bgfx,jpcy/bgfx,mendsley/bgfx,attilaz/bgfx,mendsley/bgfx,mendsley/bgfx,emoon/bgfx,emoon/bgfx,LWJGL-CI/bgfx,bkaradzic/bgfx,jpcy/bgfx,jdryg/bgfx,jdryg/bgfx,MikePopoloski/bgfx,emoon/bgfx,bkaradzic/bgfx,jdryg/bgfx