i915/perf: Store a mask of valid OA formats for a platform

Validity of an OA format is checked by using a sparse array of formats
per gen. Instead maintain a mask of supported formats for a platform in
the perf object.

v2: Use set_bit and test_bit style for the format_mask (Chris)

Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210208174029.45621-1-umesh.nerlige.ramappa@intel.com