powercap: RAPL: Fix a NULL vs IS_ERR() bug

mainline inclusion
from mainline-v6.5-rc1
commit 49776c71
category: bugfix
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I92135

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=49776c712eb6ded12fcbb8cc915a498dbfb47311



--------------------------------

The devm_ioremap_resource() function returns error pointers on error,
it never returns NULL.  Update the check accordingly.

Intel-SIG: commit 49776c71 powercap: RAPL: Fix a NULL vs IS_ERR() bug.
Backport Intel RAPL driver support on TPMI.

Fixes: 9eef7f9d ("powercap: intel_rapl: Introduce RAPL TPMI interface driver")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
[ Xiaolong Wang: amend commit log ]
Signed-off-by: Xiaolong Wang <xiaolong.wang@intel.com>