Revert "remove some warnings"

This reverts commit d35fb3e535c380e81222465dc72a2e1cd82e4521.
Revert "OMAP4430/60: EMIF: errata i743: Prohibit usage of Power-Down mode"

This reverts commit fe76188e3856f793a3a0fe64e992704ec705d1b4.
ARM: OMAP4: EMIF: implementation of errata i735 for PM timer

EMIF Power Management timer for Self Refresh will put the external SDRAM
in Self Refresh mode after the EMIF is idle for number of DDR clock cycles
that is set with REG_SR_TIM. The minimal value starts at 16 cycles.
However due to Errata i735, the minimal value is 512 DDR cycles as it is
required at OPP100 frequency.

Change-Id: If0748903580877aa4c1803f47e9134ee60c1dd75
Signed-off-by: Konstantyn Shlyakhovoy <x0155534@ti.com>

Conflicts:
	arch/arm/mach-omap2/emif.c