kconfig: Do not print status messages in make -s mode

Add an -s option to the various frontends and pass it when make -s is
used. Also, use $(kecho) instead of @echo in the Makefile.

Signed-off-by: Michal Marek <mmarek@suse.cz>
Git-commit: 0a1f00a1c86421cc07cec87011c7cf4df68ee54b
Git-repo: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git


Change-Id: If6f365ae189f6ef2dd515793f4fb46e6bd9e31ef
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>