MIPS: kernel: entry.S: Set correct ISA level for mips_ihb

Commit 6ebb496ffc7e("MIPS: kernel: entry.S: Add MIPS R6 related
definitions") added the MIPSR6 definition but it did not update the
ISA level of the actual assembly code so a pre-MIPSR6 jr.hb instruction
was generated instead. Fix this by using the MISP_ISA_LEVEL_RAW macro.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Fixes: 6ebb496ffc7e("MIPS: kernel: entry.S: Add MIPS R6 related definitions")
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9386/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/kernel/entry.S

@@ -10,6 +10,7 @@
 
 #include <asm/asm.h>
 #include <asm/asmmacro.h>
+#include <asm/compiler.h>
 #include <asm/regdef.h>
 #include <asm/mipsregs.h>
 #include <asm/stackframe.h>
@@ -185,7 +186,7 @@ syscall_exit_work:
  * For C code use the inline version named instruction_hazard().
  */
 LEAF(mips_ihb)
-	.set	mips32r2
+	.set	MIPS_ISA_LEVEL_RAW
 	jr.hb	ra
 	nop
 	END(mips_ihb)