usb: gadget: s3c-hsotg: fix build on x86 and other architectures

The readsl and writesl I/O accessors are only defined on some
architectures. The driver currently depends on CONFIG_ARM because
the build breaks on x86, in particular. Switch to use of ioread32_rep
and iowrite32_rep to fix build on all architectures and remove the
CONFIG_ARM dependency.

Also update printk formatting to handle a long long dma_addr_t to avoid
warnings on !32-bit architectures.

Signed-off-by: Matt Porter <mporter@linaro.org>
Signed-off-by: Felipe Balbi <balbi@ti.com>