libexfat: remove unneeded -Werror and adding -lc

Signed-off-by: Nicolas Boos <nicolas.boos@wanadoo.fr>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
diff --git a/lib/Makefile.am b/lib/Makefile.am
index 6277665..5ea12db 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -1,7 +1,4 @@
-AM_CFLAGS = -Wall -Werror -Wunused-parameter \
-	    -Wno-address-of-packed-member \
-	    -include $(top_builddir)/config.h -I$(top_srcdir)/include -fno-common
-LIBS = -lc
+AM_CFLAGS = -Wall -include $(top_builddir)/config.h -I$(top_srcdir)/include -fno-common
 noinst_LIBRARIES = libexfat.a
 
 libexfat_a_SOURCES = libexfat.c