[SYCL][Bindless] Add support for mipmap data types smaller than 32-bit (#10856)

This commit adds support for data types smaller then 32-bit for mipmaps.

The added types are short, short2, short4, ushort, ushort2, ushort4,
char, char2, char4, uchar, uchar2, uchar4, half, half2, and half4.
Mipmap tests have been modified to test all valid data types. `image.cl`
has also been refactored to reduce code duplication.

Author: DBDuncan