watchdog: JZ4740: Remove dependency towards arch header timer.h

This allows this driver to be used for other JZ47xx platforms,
that won't provide this header.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
MIPS: JZ4770: Add a 0x10 offset to the base address of the TCU

The first 0x10 bytes are reserved for the watchdog registers.

This patch also adds a constant that defines the base of the
watchdog registers.
watchdog: Allow selection of jz4740-wdt driver on jz4770 archs
MIPS: JZ4770: Added platform data for the jz4740-wdt watchdog driver
MIPS: JZ4770: GCW0: Enable jz4740-wdt watchdog driver
fb: JZ4770: Display the current logo at the end of the probe function
MIPS: JZ4770: Add GCW-Zero / OpenDingux logo
opendingux: Ensure that the modules FS works with -dirty kernel versions
MIPS: JZ4770: GCW0: Increase GPIO debounce for OTG

A higher debounce timeout seems required for proper detection of
hot-plug events.
cpufreq: JZ4770: Increase transition latency

A transition latency of 200us is apparently not enough, as it seems
to be crashing the SoC on some setups. No issues were reported with
a transition latency of 400us, so I'm switching to that value from
now on.
MIPS: JZ4770: GCW0: defconfig: Enable watchdog, logo, CPUfreq driver