mtd-utils: various fixes, apply OpenEmbedded patches

[David Oberhollenzer]

Hi,

Thanks for the pointers. I took a look at the buildroot patches.

The first one (ubinize return status) has been applied shortly after
the mtd-utils 1.5.2 release.

The second patch (about execinfo.h) sparked a discussion with Richard
prefering a libmissing implementation instead. A libmissing has been
added in August last year that provides a dummy implementation of the
backtrace family of functions for libraries like musl that don't
provided them.

The third patch, that removes the bits/stdio_lim.h inclusion was also
applied already between the 1.5.2 and 2.0.0-rc1 releases.


Thanks,

David