phy: HiSilicon: Fix copy and paste bug in error handling

This should check ">pmctrl" instead of "->sysctrl".  This bug could
potentially lead to a crash if we dereference the error pointer.

Fixes: 73075011 ("phy: HiSilicon: Add driver for Kirin 970 PCIe PHY")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/20211117074843.GE5237@kili


Signed-off-by: Vinod Koul <vkoul@kernel.org>