gnu: gdb-minimal: Include guile.

* gnu/packages/gdb.scm (gdb-minimal): Do not remove guile, as it is a cheap
and very useful dependency.

gnu/packages/gdb.scm

@@ -164,5 +164,4 @@ written in C, C++, Ada, Objective-C, Pascal and more.")
    gdb-9.2
    (name "gdb-minimal")
    (inputs (fold alist-delete (package-inputs gdb)
-                 '("guile" "libxml2" "ncurses" "python-wrapper"
-                   "source-highlight")))))
+                 '("libxml2" "ncurses" "python-wrapper" "source-highlight")))))