This patch updates the board specific USB support
code for the sh7372 Mackerel board.

With this patch applied port CN22 is driven by the
recently added renesas_usbhs driver using the first
USB controller included in sh7372 aka USBHS0.

Hotplugging of USBHS0 unfortunately has to be
handled by software polling. The sh7372 SoC itself
obviously supports hotplug notification by IRQ but
on the Mackerel board this IRQ happens to be used
for the touch screen.

Also fix the pinmux configuration to avoid setting
up unused pins and fix minor spelling errors.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>