[PATCH build machinery]: Fix PR bootstrap/42424, in-tree GMP/MPFR/MPC bootstrap fails

[Paolo Bonzini]

> diff -rup orig/egcc-SVN20100106/configure.ac egcc-SVN20100106/configure.ac
> --- orig/egcc-SVN20100106/configure.ac	2010-01-03 02:01:25.000000000 +0100
> +++ egcc-SVN20100106/configure.ac	2010-01-06 20:05:24.000000000 +0100
> @@ -23,6 +23,11 @@ m4_include(config/acx.m4)
>   m4_include(config/override.m4)
>   m4_include(config/proginstall.m4)
>   m4_include(config/elf.m4)
> +m4_include([libtool.m4])
> +m4_include([ltoptions.m4])
> +m4_include([ltsugar.m4])
> +m4_include([ltversion.m4])
> +m4_include([lt~obsolete.m4])

Please check if you can include only libtool.m4.  Otherwise ok, thanks!

Paolo