Add IMG_tile_region_protection extension for GLSC 2.0

[DeepakRavikumarIMG]

This extension for OpenGL SC2.0 allows applications to tag all its safety-critical geometric primitives as safety-related in order to run safety integrity checks on them when rendering them on Imagination Technologies safety-critical Tile Based rendering GPUs.

[oddhack]

This should also update index_sc.php to add a subsection header and include of extensions/scext.php, something like the "otherextspecs" section of index_es.php. Otherwise, this is good.

[DeepakRavikumarIMG]

This should also update index_sc.php to add a subsection header and include of extensions/scext.php, something like the "otherextspecs" section of index_es.php. Otherwise, this is good.

Thanks, this is fixed.

[oddhack]

LGTM - when @pdaniell-nv signs it off I'll merge this.

[pdaniell-nv]

This vendor extension is approved to merge.