fix minor bug in opengl1 framebuffer
fix minor bug in opengl1 framebuffer

Cavitt/otclient_mapgen,kwketh/otclient,EvilHero90/otclient,kwketh/otclient,gpedro/otclient,gpedro/otclient,dreamsxin/otclient,dreamsxin/otclient,dreamsxin/otclient,Radseq/otclient,gpedro/otclient,Radseq/otclient,Cavitt/otclient_mapgen,EvilHero90/otclient