cpufreq: amd-pstate: Cap the CPPC.max_perf to nominal_perf if CPB is off

When Core Performance Boost is disabled by the user, the
CPPC_REQ.max_perf should not exceed the nominal_perf since by definition
the frequencies between nominal_perf and the highest_perf are in the
boost range. Fix this in amd_pstate_update()

Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
Link: https://lore.kernel.org/r/66f55232be01092c423f0523f68b82b80c293943.1718988436.git.perry.yuan@amd.com
Link: https://lore.kernel.org/r/20240626042733.3747-4-mario.limonciello@amd.com


Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>