ARM: OMAP2+: Fix possible memory leak in omap_hwmod_allocate_module

Fix memory leak in omap_hwmod_allocate_module not freeing in
handling error path.

Fixes: 8c879705

("ARM: OMAP2+: Add functions to allocate module data from device tree")
Signed-off-by: Chen Tao <chentao107@huawei.com>
Reviewed-by: Paul Walmsley <paul@pwsan.com>
[tony@atomide.com: fix call iounmap for missing regs]
Signed-off-by: Tony Lindgren <tony@atomide.com>