ARM: omap1: fix !ARCH_OMAP1_ANY link failures

While compile-testing randconfig builds for the upcoming boardfile
removal, I noticed that an earlier patch of mine was completely
broken, and the introduction of CONFIG_ARCH_OMAP1_ANY only replaced
one set of build failures with another one, now resulting in
link failures like

ld: drivers/video/fbdev/omap/omapfb_main.o: in function `omapfb_do_probe':
drivers/video/fbdev/omap/omapfb_main.c:1703: undefined reference to `omap_set_dma_priority'
ld: drivers/dma/ti/omap-dma.o: in function `omap_dma_free_chan_resources':
drivers/dma/ti/omap-dma.c:777: undefined reference to `omap_free_dma'
drivers/dma/ti/omap-dma.c:1685: undefined reference to `omap_get_plat_info'
ld: drivers/usb/gadget/udc/omap_udc.o: in function `next_in_dma':
drivers/usb/gadget/udc/omap_udc.c:820: undefined reference to `omap_get_dma_active_status'

I tried reworking it, but the resulting patch ended up much bigger than
simply avoiding the original problem of unused-function warnings like

arch/arm/mach-omap1/mcbsp.c:76:30: error: unused variable 'omap1_mcbsp_ops' [-Werror,-Wunused-variable]

As a result, revert the previous fix, and rearrange the code that
produces warnings to hide them. For mcbsp, the #ifdef check can
simply be removed as the cpu_is_omapxxx() checks already achieve
the same result, while in the io.c the easiest solution appears to
be to merge the common map bits into each soc specific portion.
This gets cleaned in a nicer way after omap7xx support gets dropped,
as the remaining SoCs all have the exact same I/O map.

Fixes: 615dce5bf736 ("ARM: omap1: fix build with no SoC selected")
Cc: stable@vger.kernel.org
Acked-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: omap1: fix build with no SoC selected

In a multiplatform randconfig kernel, one can have
CONFIG_ARCH_OMAP1 enabled, but none of the specific SoCs.
This leads to some build issues as the code is not
meant to deal with this configuration at the moment:

arch/arm/mach-omap1/io.c:86:20: error: unused function 'omap1_map_common_io' [-Werror,-Wunused-function]
arch/arm/mach-omap1/pm.h:113:2: error: "Power management for this processor not implemented yet" [-Werror,-W#warnings]

Use the same trick as on OMAP2 and guard the actual compilation
of platform code with another Makefile ifdef check based
on an option that depends on having at least one SoC enabled.

The io.c file still needs to get compiled to allow building
device drivers with a dependency on CONFIG_ARCH_OMAP1.

Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: omap1: move some headers to include/linux/soc

There are three remaining header files that are used by omap1
specific device drivers:

- mach/soc.h provides cpu_is_omapXXX abstractions
- mach/hardware.h provides omap_read/omap_write functions
and physical addresses
- mach/mux.h provides an omap specific pinctrl abstraction

This is generally not how we do platform abstractions today,
and it would be good to completely get rid of these in favor
of passing information through platform devices and the pinctrl
subsystem.

However, given that nobody is working on that, just move it
one step forward by splitting out the header files that are
used by drivers today from the machine headers that are only
used internally.

Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>