kconfig/lxdialog: refactor color support

Clean up and refactor color support. All color support are now
in util.c including color definitions.
In the process introduced a global variable named 'dlg' which is
used all over to set color - thats the reason why all files are changed.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

diff --cc scripts/kconfig/lxdialog/checklist.c
Simple merge

diff --cc scripts/kconfig/lxdialog/colors.h
Simple merge

diff --cc scripts/kconfig/lxdialog/dialog.h
Simple merge

diff --cc scripts/kconfig/lxdialog/inputbox.c
Simple merge

diff --cc scripts/kconfig/lxdialog/lxdialog.c
Simple merge

diff --cc scripts/kconfig/lxdialog/menubox.c
Simple merge

diff --cc scripts/kconfig/lxdialog/msgbox.c
Simple merge

diff --cc scripts/kconfig/lxdialog/textbox.c
Simple merge

diff --cc scripts/kconfig/lxdialog/util.c
Simple merge

diff --cc scripts/kconfig/lxdialog/yesno.c
Simple merge