ARM: OMAP2+: GPMC: Export gpmc_enable_hwecc and gpmc_calculate_ecc

To be able to compile kernel/drivers/mtd/nand/omap2.ko as module, that
two symbols need to be exported. Otherwise, I get following error
message

    ERROR: "gpmc_calculate_ecc" [drivers/mtd/nand/omap2.ko] undefined!
    ERROR: "gpmc_enable_hwecc" [drivers/mtd/nand/omap2.ko] undefined!
Signed-off-by: Bernhard Walle <walle@corscience.de>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/mach-omap2/gpmc.c

@@ -888,6 +888,7 @@ int gpmc_enable_hwecc(int cs, int mode, int dev_width, int ecc_size)
 	gpmc_write_reg(GPMC_ECC_CONFIG, val);
 	return 0;
 }
+EXPORT_SYMBOL_GPL(gpmc_enable_hwecc);
 
 /**
  * gpmc_calculate_ecc - generate non-inverted ecc bytes
@@ -918,3 +919,4 @@ int gpmc_calculate_ecc(int cs, const u_char *dat, u_char *ecc_code)
 	gpmc_ecc_used = -EINVAL;
 	return 0;
 }
+EXPORT_SYMBOL_GPL(gpmc_calculate_ecc);