[2.2.9 RC1] Software to OpenGL renderswap level transition sigsegv

How to reproduce:

Crash log: srb2prerelease.RPT

happens in both rc1 and latest next but not in 2.2.8

changed title from [2.2.9 RC1] Renderswap level transition sigsegv to [2.2.9 RC1] Software to OpenGL renderswap level transition sigsegv

Here's a backtrace:

(gdb) bt
#0  DeleteTexture@4 (pTexInfo=0x1a3be9a0) at hardware/r_opengl/r_opengl.c:1300
#1  0x005c4c9e in HWR_FreeTextureData (patch=0x1a3993c0)
    at hardware/hw_cache.c:598
#2  HWR_FreeTexture (patch=patch@entry=0x1a3993c0) at hardware/hw_cache.c:616
#3  0x005734b8 in Patch_FreeData (patch=patch@entry=0x1a3993c0)
    at r_patch.c:74
#4  0x0057385f in Patch_Free (patch=0x1a3993c0) at r_patch.c:107
#5  0x0046315c in Y_UnloadData () at y_inter.c:2060
#6  0x00465af3 in Y_EndIntermission () at y_inter.c:2036

added Bug Regression OpenGL renderer labels

mentioned in merge request !1448 (merged)

closed via merge request !1448 (merged)

mentioned in commit d18ef874