Add Missing `ur_device_affinity_domain_flag_t` Enumerations

[FranklandJack]

Issue

PI defines the pi_device_affinity_domain bitfield which can take the following values:

• PI_DEVICE_AFFINITY_DOMAIN_L4_CACHE
• PI_DEVICE_AFFINITY_DOMAIN_L3_CACHE
• PI_DEVICE_AFFINITY_DOMAIN_L2_CACHE
• PI_DEVICE_AFFINITY_DOMAIN_L1_CACHE

which are used here, here, here and here respectively in the DPC++ runtime.

Unified Runtime defines the ur_device_affinity_domain_flag_t enumeration but it is missing the above values.

Task

Add the missing enumerations from above to Unified Runtime so that it meets the requirements of the DPC++ runtime.

[FranklandJack]

There is a bit of a question of whether the DPC++ runtime actually needs to use these enumerations, see the comments on https://github.com/oneapi-src/unified-runtime/pull/132.

[FranklandJack]

Since these enumeration values aren't used outside the DPC++ codebase, it probably doesn't make sense to add them to UR and instead they should be pulled into the DPC++ headers so they can be reused in that codebase.

[kbenzie]

These enums are likely not required for UR.

I don't think I agree, they are required for the SYCL 2020 spec, see table 23.