perf/x86/rapl: Move the pmu allocation out of CPU hotplug

There are extra codes in the CPU hotplug function to allocate rapl pmus.
The generic PMU hotplug support is hard to be applied.

As long as the rapl pmus can be allocated upfront for each die/socket,
the code doesn't need to be implemented in the CPU hotplug function.
Move the code to the init_rapl_pmus(), and allocate a PMU for each
possible die/socket.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Oliver Sang <oliver.sang@intel.com>
Link: https://lore.kernel.org/r/20241010142604.770192-1-kan.liang@linux.intel.com