ARM: pxa: fix building without IWMMXT

When CONFIG_IWMMXT, the pxa3xx and pxa27x suspend/resume code
emits some xscale specific instructions, which are rejected
by the assembler, because gcc is built with -march=armv5
-mtune=xscale and passes that option to the assembler:

/tmp/cciHumzr.s:553: Error: selected processor does not support ARM mode `mra r2,r3,acc0'
/tmp/cciHumzr.s:605: Error: selected processor does not support ARM mode `mar acc0,r2,r3'
make[3]: *** [arch/arm/mach-pxa/pxa3xx.o] Error 1
/tmp/cci5MUNu.s:326: Error: selected processor does not support ARM mode `mra r2,r3,acc0'
/tmp/cci5MUNu.s:367: Error: selected processor does not support ARM mode `mar acc0,r2,r3'
make[3]: *** [arch/arm/mach-pxa/pxa27x.o] Error 1

Overriding with -Wa,-march=xscale no longer works, so instead
I'm adding an explict ".arch_extension" directive in all four inline
assembly statements, which should work even if they end up in a different
order in the assembly output.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>

arch/arm/mach-pxa/pxa27x.c

@@ -132,7 +132,8 @@ void pxa27x_cpu_pm_enter(suspend_state_t state)
 #ifndef CONFIG_IWMMXT
 	u64 acc0;
 
-	asm volatile("mra %Q0, %R0, acc0" : "=r" (acc0));
+	asm volatile(".arch_extension xscale\n\t"
+		     "mra %Q0, %R0, acc0" : "=r" (acc0));
 #endif
 
 	/* ensure voltage-change sequencer not initiated, which hangs */
@@ -151,7 +152,8 @@ void pxa27x_cpu_pm_enter(suspend_state_t state)
 	case PM_SUSPEND_MEM:
 		cpu_suspend(pwrmode, pxa27x_finish_suspend);
 #ifndef CONFIG_IWMMXT
-		asm volatile("mar acc0, %Q0, %R0" : "=r" (acc0));
+		asm volatile(".arch_extension xscale\n\t"
+			     "mar acc0, %Q0, %R0" : "=r" (acc0));
 #endif
 		break;
 	}

arch/arm/mach-pxa/pxa3xx.c

@@ -102,7 +102,8 @@ static void pxa3xx_cpu_pm_suspend(void)
 #ifndef CONFIG_IWMMXT
 	u64 acc0;
 
-	asm volatile("mra %Q0, %R0, acc0" : "=r" (acc0));
+	asm volatile(".arch_extension xscale\n\t"
+		     "mra %Q0, %R0, acc0" : "=r" (acc0));
 #endif
 
 	/* resuming from D2 requires the HSIO2/BOOT/TPM clocks enabled */
@@ -130,7 +131,8 @@ static void pxa3xx_cpu_pm_suspend(void)
 	AD3ER = 0;
 
 #ifndef CONFIG_IWMMXT
-	asm volatile("mar acc0, %Q0, %R0" : "=r" (acc0));
+	asm volatile(".arch_extension xscale\n\t"
+		     "mar acc0, %Q0, %R0" : "=r" (acc0));
 #endif
 }