kconfig: be more helpful if pkg-config is missing

If ncurses is installed, but at a non-default location, the previous
error message was not helpful in resolving the situation.  Now it will
suggest that pkg-config might need to be installed in addition to
ncurses.
Signed-off-by: NAlyssa Ross <hi@alyssa.is>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

scripts/kconfig/mconf-cfg.sh

@@ -44,4 +44,7 @@ echo >&2 "* Unable to find the ncurses package."
 echo >&2 "* Install ncurses (ncurses-devel or libncurses-dev"
 echo >&2 "* depending on your distribution)."
 echo >&2 "*"
+echo >&2 "* You may also need to install pkg-config to find the"
+echo >&2 "* ncurses installed in a non-default location."
+echo >&2 "*"
 exit 1

scripts/kconfig/nconf-cfg.sh

@@ -44,4 +44,7 @@ echo >&2 "* Unable to find the ncurses package."
 echo >&2 "* Install ncurses (ncurses-devel or libncurses-dev"
 echo >&2 "* depending on your distribution)."
 echo >&2 "*"
+echo >&2 "* You may also need to install pkg-config to find the"
+echo >&2 "* ncurses installed in a non-default location."
+echo >&2 "*"
 exit 1