RFC: Use same gdb on RTEMS 5 as RTEMS 6

[Joel Sherrill]

Hi

The gdb version (9.x)  we are using for RTEMS 5 tools does not build
on Cygwin and hasn't for a while.

https://sourceware.org/bugzilla/show_bug.cgi?id=26757

I looked at bumping minor revisions in the gdb 9 series but they still
don't build. Using the same gdb 10 configuration we use on rtems 6
does build.

I haven't found a patch that applies cleanly from a trusted source. I
could create one but I really feel more comfortable just bumping to
gdb 10.

Any thoughts before I file a ticket and propose a patch?

--joel