safeclib: fix trailing whitespace

Fixes trailing whitespace after MIT

Fixes:
 - https://gitlab.com/buildroot.org/buildroot/-/jobs/50971692

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Acked-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/safeclib/safeclib.mk

@@ -6,7 +6,7 @@
 
 SAFECLIB_VERSION = v09102017
 SAFECLIB_SITE = $(call github,rurban,safeclib,$(SAFECLIB_VERSION))
-SAFECLIB_LICENSE = MIT 
+SAFECLIB_LICENSE = MIT
 SAFECLIB_LICENSE_FILES = COPYING
 SAFECLIB_INSTALL_STAGING = YES
 # From git