configure: rationalise error messages with meaningful texts
Currently, error messages just state the obvious: a required
component is required. While in some cases, there is not much
else to say, in some other cases we could tell much more.
For example, a missing libstdc++ means no static toolchain.
Also, format error and warning messages in a similar fashion,
with a {error,warning} intro, followed by the message specified
by the caller.
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>
1 This is NOT the official version of dialog. This version has been
2 significantly modified from the original. It is for use by the Linux
3 kernel configuration script. Please do not bother Savio Lam with