package/madplay: force arm mode instead of Thumb mode

Fix the following build failure raised because madplay uses mad_f_mul
which is defined in usr/include/mad.h (installed by libmad which has
been fixed by a similar workaround in commit
0aaadd525f2df02911349ffe1518814fa095bf96, unfortunately the fix works
for compiled code, not mad_f_mul define):

/tmp/cc5SGGoU.s:102: Error: selected processor does not support `smull r8,r9,r2,r4' in Thumb mode

Fixes:
 - http://autobuild.buildroot.org/results/0c0955d4f6726b50cad721f4d3437dabde316e70

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
(cherry picked from commit a9da69260691bb692d7a2f0417fc5f52bcf45b5e)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/madplay/madplay.mk

@@ -15,6 +15,14 @@ MADPLAY_DEPENDENCIES = host-pkgconf libmad libid3tag $(TARGET_NLS_DEPENDENCIES)
 # Also 0003-configure-ac-use-pkg-config-to-find-id3tag.patch
 MADPLAY_AUTORECONF = YES
 
+# madplay uses libmad which has some assembly function that is not present in
+# Thumb mode:
+# Error: selected processor does not support `smull r8,r9,r2,r4' in Thumb mode
+# so, we desactivate Thumb mode
+ifeq ($(BR2_ARM_INSTRUCTIONS_THUMB),y)
+MADPLAY_CONF_ENV += CFLAGS="$(TARGET_CFLAGS) -marm"
+endif
+
 # Check if ALSA is built, then we should configure after alsa-lib so
 # ./configure can find alsa-lib.
 ifeq ($(BR2_PACKAGE_MADPLAY_ALSA),y)