env: make env drivers propagate env_import return value

For multiple env drivers to correctly implement fallback when
one environment fails to load (e.g. crc error), the return value
of env_import has to be propagated by all env driver's load
function.

Without this change, the first driver that succeeds to load an
environment with an invalid CRC return 0 (success) and no other
drivers are checked.

Signed-off-by: Simon Goldschmidt <sgoldschmidt@de.pepperl-fuchs.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>

env/flash.c

@@ -351,9 +351,7 @@ static int env_flash_load(void)
 		     "reading environment; recovered successfully\n\n");
 #endif /* CONFIG_ENV_ADDR_REDUND */
 
-	env_import((char *)flash_addr, 1);
-
-	return 0;
+	return env_import((char *)flash_addr, 1);
 }
 #endif /* LOADENV */