package/pkg-kconfig: fix error string

Current error string speaks only about "fragment" but here we also deal
with Kconfig files, so let's add "file or fragment" instead of "fragment".

Signed-off-by: Giulio Benetti <giulio.benetti@benettiengineering.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
(cherry picked from commit a7348f0f7de1021ea578cd81784e70b1832adb79)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/pkg-kconfig.mk

@@ -117,7 +117,7 @@ $(2)_KCONFIG_STAMP_DOTCONFIG = .stamp_dotconfig
 $$($(2)_KCONFIG_FILE) $$($(2)_KCONFIG_FRAGMENT_FILES): | $(1)-patch
 	for f in $$($(2)_KCONFIG_FILE) $$($(2)_KCONFIG_FRAGMENT_FILES); do \
 		if [ ! -f "$$$${f}" ]; then \
-			printf "Kconfig fragment '%s' for '%s' does not exist\n" "$$$${f}" "$(1)"; \
+			printf "Kconfig file or fragment '%s' for '%s' does not exist\n" "$$$${f}" "$(1)"; \
 			exit 1; \
 		fi; \
 	done