gunzip: move to lib_generic

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
diff --git a/lib_generic/Makefile b/lib_generic/Makefile
index bf0e31d..a820f97 100644
--- a/lib_generic/Makefile
+++ b/lib_generic/Makefile
@@ -34,6 +34,7 @@
 COBJS-y += ctype.o
 COBJS-y += display_options.o
 COBJS-y += div64.o
+COBJS-y += gunzip.o
 COBJS-y += lmb.o
 COBJS-y += ldiv.o
 COBJS-$(CONFIG_MD5) += md5.o