Revert "generic: mtd: spi-nor: always disable software protection"

This reverts commit 1ccd24df.

This commit probably causes problems with some flash chips:

http://patchwork.ozlabs.org/patch/549173/
http://patchwork.ozlabs.org/patch/553683/

patches/openwrt/0020-generic-mtd-spi-nor-always-disable-software-protection.patch

-From: Matthias Schiffer <mschiffer@universe-factory.net>
-Date: Sat, 26 Mar 2016 13:20:41 +0100
-Subject: generic: mtd: spi-nor: always disable software protection
-
-Fixes unwriteable flash when the bootloader leaves it protected.
-
-diff --git a/target/linux/generic/patches-3.18/462-m25p80-always-disable-software-protection.patch b/target/linux/generic/patches-3.18/462-m25p80-always-disable-software-protection.patch
-new file mode 100644
-index 0000000..7be7d0f
---- /dev/null
-+++ b/target/linux/generic/patches-3.18/462-m25p80-always-disable-software-protection.patch
-@@ -0,0 +1,22 @@
-+--- a/drivers/mtd/spi-nor/spi-nor.c
-++++ b/drivers/mtd/spi-nor/spi-nor.c
-+@@ -957,15 +957,11 @@ int spi_nor_scan(struct spi_nor *nor, co
-+ 
-+ 	/*
-+ 	 * Atmel, SST and Intel/Numonyx serial nor tend to power
-+-	 * up with the software protection bits set
-++	 * up with the software protection bits set;
-++	 * others may be left protected by the bootloader
-+ 	 */
-+-
-+-	if (JEDEC_MFR(info->jedec_id) == CFI_MFR_ATMEL ||
-+-	    JEDEC_MFR(info->jedec_id) == CFI_MFR_INTEL ||
-+-	    JEDEC_MFR(info->jedec_id) == CFI_MFR_SST) {
-+-		write_enable(nor);
-+-		write_sr(nor, 0);
-+-	}
-++	write_enable(nor);
-++	write_sr(nor, 0);
-+ 
-+ 	if (!mtd->name)
-+ 		mtd->name = dev_name(dev);
-diff --git a/target/linux/generic/patches-3.18/462-m25p80-mx-disable-software-protection.patch b/target/linux/generic/patches-3.18/462-m25p80-mx-disable-software-protection.patch
-deleted file mode 100644
-index d7d7eec..0000000
---- a/target/linux/generic/patches-3.18/462-m25p80-mx-disable-software-protection.patch
-+++ /dev/null
-@@ -1,10 +0,0 @@
----- a/drivers/mtd/spi-nor/spi-nor.c
--+++ b/drivers/mtd/spi-nor/spi-nor.c
--@@ -962,6 +962,7 @@ int spi_nor_scan(struct spi_nor *nor, co
-- 
-- 	if (JEDEC_MFR(info->jedec_id) == CFI_MFR_ATMEL ||
-- 	    JEDEC_MFR(info->jedec_id) == CFI_MFR_INTEL ||
--+	    JEDEC_MFR(info->jedec_id) == CFI_MFR_MACRONIX ||
-- 	    JEDEC_MFR(info->jedec_id) == CFI_MFR_SST) {
-- 		write_enable(nor);
-- 		write_sr(nor, 0);