classpath: fix alsa-related build failure

Classpath requires sequencer support besides pcm support. Fixes:
http://autobuild.buildroot.org/results/2bd/2bd39ffa821bc02d64998bc9e8fe178d3741a1d8/

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

package/classpath/classpath.mk

@@ -22,7 +22,9 @@ CLASSPATH_AUTORECONF = YES
 CLASSPATH_LICENSE = GPLv2+ with exception
 CLASSPATH_LICENSE_FILES = COPYING
 
-ifeq ($(BR2_PACKAGE_ALSA_LIB),y)
+# Needs ALSA pcm and sequencer (midi) support
+# pcm is always on for alsa-lib
+ifeq ($(BR2_PACKAGE_ALSA_LIB_SEQ),y)
 CLASSPATH_CONF_OPT += --enable-alsa
 CLASSPATH_DEPENDENCIES += alsa-lib
 else