package/libev: force arm mode instead of Thumb mode

Fix the following build failure:

/tmp/ccHc3Awn.s:825: Error: selected processor does not support `mcr p15,0,r3,c7,c10,5' in Thumb mode

Fixes:
 - http://autobuild.buildroot.org/results/1c597c9da724d6cac06b09b1ecd456a28440a3a3

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Arnout Vandecappelle <arnout@mind.be>
(cherry picked from commit 964254bfd99a5bb7c405a03bdd165f11ddc36f4a)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/libev/libev.mk

@@ -10,6 +10,13 @@ LIBEV_INSTALL_STAGING = YES
 LIBEV_LICENSE = BSD-2-Clause or GPL-2.0+
 LIBEV_LICENSE_FILES = LICENSE
 
+# libev has some assembly function that is not present in Thumb mode:
+# Error: selected processor does not support `mcr p15,0,r3,c7,c10,5' in Thumb mode
+# so, we desactivate Thumb mode
+ifeq ($(BR2_ARM_INSTRUCTIONS_THUMB),y)
+LIBEV_CONF_ENV += CFLAGS="$(TARGET_CFLAGS) -marm"
+endif
+
 # The 'compatibility' event.h header conflicts with libevent
 # It's completely unnecessary for BR packages so remove it
 define LIBEV_DISABLE_EVENT_H_INSTALL