ar71xx: boost SPI flash read performance

mtd_speedtest results:
                           page read speed
                    old         new        delta
DB120            929 KiB/s   2597 KiB/s   +179.55%
TL-WR1043ND v1   754 KiB/s   2166 KiB/s   +187.27%
TL-WR703N v1     745 KiB/s   2176 KiB/s   +192.08%
TL-MR3220 v1     752 KiB/s   2154 KiB/s   +186.44%
TL-WR2543ND v1   564 KiB/s   2130 KiB/s   +277.66%
TL-WR741ND v2    525 KiB/s   1767 KiB/s   +236.57%
ALFA-AP96        702 KiB/s   1977 KiB/s   +181.62%
WNDR3700         697 KiB/s   1965 KiB/s   +181.92%

SVN-Revision: 31118

1 files changed, 1 insertions, 0 deletions

diff --git a/target/linux/ar71xx/files/arch/mips/ath79/dev-m25p80.c b/target/linux/ar71xx/files/arch/mips/ath79/dev-m25p80.c
index 9ac19d83ae..66115b1c48 100644
--- a/target/linux/ar71xx/files/arch/mips/ath79/dev-m25p80.c
+++ b/target/linux/ar71xx/files/arch/mips/ath79/dev-m25p80.c
@@ -51,6 +51,7 @@ void __init ath79_register_m25p80(struct flash_platform_data *pdata)
 {
 	ath79_spi_data.bus_num = 0;
 	ath79_spi_data.num_chipselect = 1;
+	ath79_spi0_cdata.is_flash = true;
 	ath79_spi_info[0].platform_data = pdata;
 	ath79_register_spi(&ath79_spi_data, ath79_spi_info, 1);
 }