Add missing sbc headers to dist
diff --git a/sbc/Makefile.am b/sbc/Makefile.am
index 5e47c77..d4ad194 100644
--- a/sbc/Makefile.am
+++ b/sbc/Makefile.am
@@ -9,6 +9,7 @@
 noinst_LTLIBRARIES = libsbc.la
 
 libsbc_la_SOURCES = sbc.h sbc.c sbc_math.h sbc_tables.h \
+	sbc_primitives.h sbc_primitives_mmx.h sbc_primitives_neon.h \
 	sbc_primitives.c sbc_primitives_mmx.c sbc_primitives_neon.c
 
 libsbc_la_CFLAGS = -finline-functions -funswitch-loops -fgcse-after-reload