mi_make_breakpoint: add "evaluated-by" option

For some time now, GDB has permitted target-side evaluation of
breakpoint conditions.  On targets that support this feature, GDB
may output an "evaluated-by" field into the breakpoint reply.

This patch adds handling for this option, and outputs a default
pattern to optionally recognize (and ignore) this pattern in the
reply.

gdb/testsuite/ChangeLog

	* lib/mi-support.exp (mi_make_breakpoint): Add option/handling for
	"evaluated-by".