perf/x86/intel/uncore: Generic uncore_get_uncores and MMIO format of SPR

Factor out SPR_UNCORE_MMIO_COMMON_FORMAT which can be reused by
Granite Rapids in the following patch.

Granite Rapids have more uncore units than Sapphire Rapids. Add new
parameters to support adjustable uncore units.

No functional change.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Ammy Yi <ammy.yi@intel.com>
Link: https://lore.kernel.org/r/20231117163939.2468007-1-kan.liang@linux.intel.com