ARM: OMAP2+: Add structure for storing GPMC settings

The GPMC has various different configuration options such as bus-width,
synchronous or asychronous mode selection, burst mode options etc.
Currently, there is no central structure for storing all these options
when configuring the GPMC for a given device. Some of the options are
stored in the GPMC timing structure and some are directly programmed
into the GPMC configuration register. Add a new structure to store
these options and convert code to use this structure. Adding this
structure will allow us to create a common function for configuring
these options.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>

arch/arm/mach-omap2/gpmc-smc91x.c

@@ -104,7 +104,7 @@ static int smc91c96_gpmc_retime(void)
 	dev_t.t_cez_w = t4_w * 1000;
 	dev_t.t_wr_cycle = (t20 - t3) * 1000;
 
-	gpmc_calc_timings(&t, &dev_t);
+	gpmc_calc_timings(&t, NULL, &dev_t);
 
 	return gpmc_cs_set_timings(gpmc_cfg->cs, &t);
 }