cpufreq/amd-pstate: Refactor amd_pstate_epp_reenable() and amd_pstate_epp_offline()

cpufreq/amd-pstate: Refactor amd_pstate_epp_reenable() and amd_pstate_epp_offline()

[ Upstream commit b1089e0c8817fda93d474eaa82ad86386887aefe ]

Replace similar code chunks with amd_pstate_update_perf() and
amd_pstate_set_epp() function calls.

Signed-off-by: Dhananjay Ugwekar <Dhananjay.Ugwekar@amd.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Link: https://lore.kernel.org/r/20241204144842.164178-4-Dhananjay.Ugwekar@amd.com
[ML: Fix LKP reported error about unused variable]
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Stable-dep-of: 3ace20038e19 ("cpufreq/amd-pstate: Fix cpufreq_policy ref counting")
Signed-off-by: Sasha Levin <sashal@kernel.org>