MIPS: SB1: Remove support for Pass 1 parts.

Pass 1 parts had a number of significant erratas and were only available
in small numbers and under NDA.  Full support also required the use of a
special toolchain that kept branches properly aligned.  These workarounds
were never upstreamed and the only toolchain known to have them is
Montavista's GCC 3.0-based toolchain which completly obsoleted if not
useless these days.

So now that automated testing has tripped over the user of the
-msb1-pass1-workarounds option, rather than fixing it remove support for
pass 1 parts.

Probably nobody will notice.  I seem to own the last know pass 1 board
and I haven't noticed another one in the wild in the past decade, at
least.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/sibyte/common/bus_watcher.c

@@ -81,10 +81,7 @@ void check_bus_watcher(void)
 {
 	u32 status, l2_err, memio_err;
 
-#ifdef CONFIG_SB1_PASS_1_WORKAROUNDS
-	/* Destructive read, clears register and interrupt */
-	status = csr_in32(IOADDR(A_SCD_BUS_ERR_STATUS));
-#elif defined(CONFIG_SIBYTE_BCM112X) || defined(CONFIG_SIBYTE_SB1250)
+#if defined(CONFIG_SIBYTE_BCM112X) || defined(CONFIG_SIBYTE_SB1250)
 	/* Use non-destructive register */
 	status = csr_in32(IOADDR(A_SCD_BUS_ERR_STATUS_DEBUG));
 #elif defined(CONFIG_SIBYTE_BCM1x55) || defined(CONFIG_SIBYTE_BCM1x80)