ARM: tegra: split tegra_pmc_init() in two

Tegra's board file currently initializes clocks much earlier than those
for most other ARM SoCs. The reason is:

* The PMC HW block is involved in the path of some interrupts (i.e. it
inverts, or not, the IRQ input pin dedicated to the PMIC).

* So, that part of the PMC must be initialized early so that the IRQ
polarity is correct.

* The PMC initialization is currently monolithic, and the PMC has some
clock inputs, so the init routine ends up calling of_clk_get_by_name(),
and hence clocks must be set up early too.

In order to defer clock initialization to the more typical location,
split out the portions of tegra_pmc_init() that are truly IRQ-related
into a separate tegra_pmc_init_irq(), which can be called from the
machine descriptor's .init_irq() function, and defer the rest until
the machine descriptor's .init_machine() function. This allows the
clock initiliazation to happen from the machine descriptor's
.init_time() function, as is typical.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
ARM: tegra: remove common.c

common.c was create to contain code shared across the various Tegra board
files. There is now only one board file, tegra.c. So, move the code there.
One exception is the PMC reboot routine, which moves to pmc.c, and now
takes advantage of the 'standard' tegra_pmc_readl/writel functions.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
ARM: tegra: delete stale header content

A few function prototypes were left in header files during code re-
organization. Delete them.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
ARM: tegra: remove tegra EMC scaling driver

Nothing calls into the Tegra EMC (External Memory Controller) scaling
driver any more, so it's dead code. Remove it.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
ARM: tegra: delete gpio-names.h

gpio-names.h defines IDs for GPIOs. This information now comes from
device tree, so delete this stale header. The one remaining use-case is
board-paz00.c's wifi_rfkill device. Isolate the knowledge of those GPIO
IDs into that file. Let's hope the values stay valid:-)

Signed-off-by: Stephen Warren <swarren@nvidia.com>
ARM: tegra: move resume vector define to irammap.h

irammap.h's purpose is to define the layout/usage of IRAM. As such,
TEGRA_IRAM_CODE_AREA should have been added there rather than iomap.h.
Move the define, and rename it something more descriptive.

Cc: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
ARM: tegra: remove much of iomap.h

iomap.h defines the base address of Tegra peripherals. Most of this
information comes from device tree now, and hence can be deleted.
Entries are kept for various system peripherals that low-level code
(such as initial boot, system suspend/resume, debug) still requires.

Removing the values removes the temptation for someone to use them.

Signed-off-by: Stephen Warren <swarren@nvidia.com>