Building an OMAP1510-only Kconfig generates the following warnings:

arch/arm/mach-omap1/pm.c: In function ¡omap1_pm_idle¢:
arch/arm/mach-omap1/pm.c:123:2: warning: #warning Enable 32kHz OS timer in order to allow sleep states in idle [-Wcpp]
 #warning Enable 32kHz OS timer in order to allow sleep states in idle
  ^
arch/arm/mach-omap1/pm.c: At top level:
arch/arm/mach-omap1/pm.c:76:23: warning: ¡enable_dyn_sleep¢ defined but not used [-Wunused-variable]
 static unsigned short enable_dyn_sleep = 0;
                       ^

These are not so easy to fix in an obviously correct fashion, since I
don't have these devices up and running in my testbed.  So, use
arch/arm/plat-omap/Kconfig and the existing pm.c source as a guide,
and posit that deep power saving states are only supported on OMAP16xx
chips with kernels built with both CONFIG_OMAP_DM_TIMER=y and
CONFIG_OMAP_32K_TIMER=y.

While here, clean up a few printk()s and unnecessary #ifdefs.

This second version of the patch incorporates several suggestions from
Jon Hunter <jgchunter@gmail.com>.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Jon Hunter <jonathanh@nvidia.com>
Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: Tuukka Tikkanen <tuukka.tikkanen@linaro.org>
Cc: Kevin Hilman <khilman@deeprootsystems.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: linux-omap@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Jon Hunter <jgchunter@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>