bootutil: Fix boot_find_status leaving flash area open

The commit fixes boot_find_status leaving flash area object in open
state on success.

Signed-off-by: Dominik Ermel <dominik.ermel@nordicsemi.no>
diff --git a/boot/bootutil/src/bootutil_misc.c b/boot/bootutil/src/bootutil_misc.c
index 19de68b..0819257 100644
--- a/boot/bootutil/src/bootutil_misc.c
+++ b/boot/bootutil/src/bootutil_misc.c
@@ -224,8 +224,9 @@
 
         off = boot_magic_off(*fap);
         rc = flash_area_read(*fap, off, magic, BOOT_MAGIC_SZ);
+        flash_area_close(*fap);
+
         if (rc != 0) {
-            flash_area_close(*fap);
             return rc;
         }
 
@@ -233,7 +234,6 @@
             return 0;
         }
 
-        flash_area_close(*fap);
     }
 
     /* If we got here, no magic was found */