phy/pxa: add HAS_IOMEM dependency

Fix this compile error:

drivers/built-in.o: In function 'mv_usb2_phy_probe':
phy-pxa-28nm-usb2.c:(.text+0x25ec): undefined reference to
'devm_ioremap_resource'
drivers/built-in.o: In function 'mv_hsic_phy_probe':
phy-pxa-28nm-hsic.c:(.text+0x3084): undefined reference to
'devm_ioremap_resource'

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>