gzip/zlib: make features optional

If you really want to slim down U-Boot and you would rather use a higher
compression scheme (like LZMA), it'd be nice to disable gzip/zlib since
these code bases take up a significant amount of space.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

common/cmd_bootm.c

@@ -352,6 +352,7 @@ static int bootm_load_os(image_info_t os, ulong *load_end, int boot_progress)
 		*load_end = load + image_len;
 		puts("OK\n");
 		break;
+#ifdef CONFIG_GZIP
 	case IH_COMP_GZIP:
 		printf ("   Uncompressing %s ... ", type_name);
 		if (gunzip ((void *)load, unc_len,
@@ -365,6 +366,7 @@ static int bootm_load_os(image_info_t os, ulong *load_end, int boot_progress)
 
 		*load_end = load + image_len;
 		break;
+#endif /* CONFIG_GZIP */
 #ifdef CONFIG_BZIP2
 	case IH_COMP_BZIP2:
 		printf ("   Uncompressing %s ... ", type_name);

include/config_defaults.h

@@ -14,4 +14,7 @@
 #define CONFIG_BOOTM_NETBSD 1
 #define CONFIG_BOOTM_RTEMS 1
 
+#define CONFIG_GZIP 1
+#define CONFIG_ZLIB 1
+
 #endif

lib_generic/Makefile

@@ -37,7 +37,7 @@ COBJS-y += crc32.o
 COBJS-y += ctype.o
 COBJS-y += display_options.o
 COBJS-y += div64.o
-COBJS-y += gunzip.o
+COBJS-$(CONFIG_GZIP) += gunzip.o
 COBJS-$(CONFIG_LMB) += lmb.o
 COBJS-y += ldiv.o
 COBJS-$(CONFIG_MD5) += md5.o
@@ -48,7 +48,7 @@ COBJS-y += string.o
 COBJS-y	+= strmhz.o
 COBJS-y += time.o
 COBJS-y += vsprintf.o
-COBJS-y += zlib.o
+COBJS-$(CONFIG_ZLIB) += zlib.o
 COBJS-$(CONFIG_RBTREE)	+= rbtree.o
 
 COBJS	:= $(COBJS-y)