MIPS: BCM47XX: Fix detected clock on Asus WL520GC and WL520GU

The Asus WL520GC and WL520GU are based on the BCM5354 and clocked at
200MHz, but they do not have a clkfreq nvram variable set to the
correct value. This adds a workaround for these devices.
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5843/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/bcm47xx/time.c

@@ -28,6 +28,7 @@
 #include <asm/time.h>
 #include <bcm47xx.h>
 #include <bcm47xx_nvram.h>
+#include <bcm47xx_board.h>
 
 void __init plat_time_init(void)
 {
@@ -35,6 +36,7 @@ void __init plat_time_init(void)
 	u16 chip_id = 0;
 	char buf[10];
 	int len;
+	enum bcm47xx_board board = bcm47xx_board_get();
 
 	/*
 	 * Use deterministic values for initial counter interrupt
@@ -64,6 +66,15 @@ void __init plat_time_init(void)
 			hz = 100000000;
 	}
 
+	switch (board) {
+	case BCM47XX_BOARD_ASUS_WL520GC:
+	case BCM47XX_BOARD_ASUS_WL520GU:
+		hz = 100000000;
+		break;
+	default:
+		break;
+	}
+
 	if (!hz)
 		hz = 100000000;