(gdb-server-prefix): New variable.

(gdb-server-prefix): New variable.
(gud-watch, gdb-send-item, gdb-breakpoints-mode, gdb-frames-mode)
(gdb-locals-mode, gdb-send-item, gdb-toggle-breakpoint)
(gdb-delete-breakpoint, gdb-frames-select, gdb-threads-buffer)
(gdb-registers-buffer, gdb-reset, gdb-assembler-buffer): Handle
new value for gud-minor-mode (gdbmi).
(gdb-buffer-type, gdb-input-queue, gdb-prompting)
(gdb-output-sink, gdb-current-item, gdb-pending-triggers): Change
from local to global gdb variable set.
(gdb-ann3): Initialise above gdb variable set.
(gdb-var-update, gdb-var-update-handler, gdb-enqueue-input)
(gdb-dequeue-input, gdb-source, gdb-pre-prompt, gdb-prompt)
(gdb-subprompt, gdb-starting, gdb-stopping, gdb-frame-begin)
(gdb-stopped, gdb-post-prompt, gdb-concat-output)
(def-gdb-auto-update-trigger, def-gdb-auto-update-handler)
(gdb-info-locals-handler, gdb-invalidate-assembler)
(gdb-get-current-frame, gdb-frame-handler): Handle gdb variable
set as global variables.
(gdb-get-create-buffer): Don't make gud-comint buffer-local.
Handle gdbmi.
(gdb-info-breakpoints-custom): Fix regexp.
(def-gdb-var): Delete.