arm: mvebu: spl: Do not build mvebu-reset in SPL

arm: mvebu: spl: Do not build mvebu-reset in SPL

Commit 35e29e89a386 ("arm: mvebu: Implement simple mvebu-reset driver
for enabling/disabling PCIe ports") made it so that the mvebu reset
driver for enabling/disabling PCIe ports is build if CONFIG_DM_RESET is
enabled. This is because PCI_MVEBU depends on DM_RESET.

But the driver should not be built for SPL. Indeed the PCI_MVEBU driver
is not supported in SPL now, and so the mvebu-reset driver is not needed.

Signed-off-by: Marek Behún <kabel@kernel.org>
Reviewed-by: Stefan Roese <sr@denx.de>