x86/cpu: Refresh DCA leaf reading code

The DCA leaf number is also hard-coded in the CPUID level dependency
table. Move its definition to common code and use it.

While at it, fix up the naming and types in the probe code.  All
CPUID data is provided in 32-bit registers, not 'unsigned long'.
Also stop referring to "level_9".  Move away from test_bit()
because the type is no longer an 'unsigned long'.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/all/20241213205032.476A30FE%40davehans-spike.ostc.intel.com