Make setenv() return status

Currently, the setenv function does not return an error code.
This patch allows to test for errors.

Signed-off-by: Steve Falco <sfalco@harris.com>

include/asm-arm/u-boot-arm.h

diff --git a/include/asm-arm/u-boot-arm.h b/include/asm-arm/u-boot-arm.h
index 41e7a8f..4ee5a32 100644
--- a/include/asm-arm/u-boot-arm.h
+++ b/include/asm-arm/u-boot-arm.h
@@ -52,7 +52,7 @@
 /* To be fixed!							*/
 /* ------------------------------------------------------------ */
 /* common/cmd_nvedit.c */
-void	setenv		(char *, char *);
+int	setenv		(char *, char *);
 
 /* cpu/.../interrupt.c */
 void	reset_timer_masked	(void);

include/common.h

diff --git a/include/common.h b/include/common.h
index 3190781..10b997e 100644
--- a/include/common.h
+++ b/include/common.h
@@ -243,9 +243,9 @@
 int	getenv_r     (char *name, char *buf, unsigned len);
 int	saveenv	     (void);
 #ifdef CONFIG_PPC		/* ARM version to be fixed! */
-void inline setenv   (char *, char *);
+int inline setenv   (char *, char *);
 #else
-void	setenv	     (char *, char *);
+int	setenv	     (char *, char *);
 #ifdef CONFIG_HAS_UID
 void	forceenv     (char *, char *);
 #endif

include/exports.h

diff --git a/include/exports.h b/include/exports.h
index d6512cb..6377875 100644
--- a/include/exports.h
+++ b/include/exports.h
@@ -22,7 +22,7 @@
 void do_reset (void);
 unsigned long simple_strtoul(const char *cp,char **endp,unsigned int base);
 char *getenv (char *name);
-void setenv (char *varname, char *varvalue);
+int setenv (char *varname, char *varvalue);
 long simple_strtol(const char *cp,char **endp,unsigned int base);
 int strcmp(const char * cs,const char * ct);
 #ifdef CONFIG_HAS_UID