MIPS: BMIPS: Fix ".previous without corresponding .section" warnings

Commit 078a55fc ("Delete __cpuinit/__CPUINIT usage from MIPS code")
removed our __CPUINIT directives, so now the ".previous" directives
are superfluous.  Remove them.
Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Cc: f.fainelli@gmail.com
Cc: mbizon@freebox.fr
Cc: jogo@openwrt.org
Cc: jfraser@broadcom.com
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8156/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/kernel/bmips_vec.S

@@ -208,7 +208,6 @@ bmips_reset_nmi_vec_end:
 END(bmips_reset_nmi_vec)
 
 	.set	pop
-	.previous
 
 /***********************************************************************
  * CPU1 warm restart vector (used for second and subsequent boots).
@@ -281,5 +280,3 @@ LEAF(bmips_enable_xks01)
 	jr	ra
 
 END(bmips_enable_xks01)
-
-	.previous