Unbind the correct texture slot in SkyManager

Wrong binding pair was introduced in 779a33ee30.

Patch By: linkmauve
Differential Revision: https://code.wildfiregames.com/D2487
This was SVN commit r23263.

binaries/data/mods/public/gui/credits/texts/programming.json

@@ -136,6 +136,7 @@
 			{"nick": "lafferjm", "name": "Justin Lafferty"},
 			{"nick": "LeanderH", "name": "Leander Hemelhof"},
 			{"nick": "leper", "name": "Georg Kilzer"},
+			{"nick": "Link Mauve", "name": "Emmanuel Gil Peyrot"},
 			{"nick": "LittleDev"},
 			{"nick": "livingaftermidnight", "name": "Will Dull"},
 			{"nick": "Louhike"},

source/renderer/SkyManager.cpp

@@ -143,7 +143,7 @@ void SkyManager::LoadSkyTextures()
 #else
 	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
 #endif
-	glBindTexture(GL_TEXTURE_2D, 0);
+	glBindTexture(GL_TEXTURE_CUBE_MAP, 0);
 	///////////////////////////////////////////////////////////////////////////
 }