PCI, vmd: Reinstate VMD driver inadvertently removed by SRCU updates

Upstream recently removed the Sleepable Read-Copy Update (SRCU) Kconfig
option (re: merge commits 8cc01d43f882 and 5dfb75e842e0; note included
commit e035e8876e6c "rcu: Remove CONFIG_SRCU").  During the back-port of
this removal series, a key patch was missed which ends up inhibiting the
ability to ever enable the Volume Management Driver (VMD) despite an
intention of such by supplying a build related '.config' file that includes
VMD's set configuration entry ("CONFIG_VMD=y").

This series resolves JIRA ticket 16633 "VMD connected drives are not visible
in system", by back-porting the missed upstream commit a8f0ff9185ae
"drivers/pci/controller: Remove "select SRCU"", thereby reinstating the
ability to include the VMD driver with the kernel.


JIRA: https://issues.redhat.com/browse/RHEL-16633
Depends: N/A

Signed-off-by: Myron Stowe <mstowe@redhat.com>