busybox: fix existing "export -n" in ash

Minor fix to existing patch which did not correctly implement -n support for the export command in ash. The VEXPORT flag of a variable was set in the first call to setvareq() and then remained set in the subsequent call, because the variable already existed in the environment.

Although /lib/functions.sh by default does not export variables (NO_EXPORT=1), this issue was leading to dirty environments.

Without this fix:
(ash) export A=1; export -n B=2; /bin/ash -c "echo \$A, \$B"
1, 2

With this fix:
(ash) export A=1; export -n B=2; /bin/ash -c "echo \$A, \$B"
1,

Signed-off-by: Christophe Lermytte <openwrt@lermytte.be>

SVN-Revision: 39968

package/utils/busybox/patches/250-ash_export-n.patch

@@ -19,7 +19,7 @@
  		aptr = argptr;
  		name = *aptr;
  		if (name) {
-@@ -12624,10 +12633,12 @@ exportcmd(int argc UNUSED_PARAM, char **
+@@ -12624,10 +12633,11 @@ exportcmd(int argc UNUSED_PARAM, char **
  					vp = *findvar(hashvar(name), name);
  					if (vp) {
  						vp->flags |= flag;
@@ -27,7 +27,7 @@
  						continue;
  					}
  				}
- 				setvar(name, p, flag);
+-				setvar(name, p, flag);
 +				setvar(name, p, flag & mask);
  			} while ((name = *++aptr) != NULL);
  			return 0;