gdb: remove unused include in infrun.c

Remove the gdbcmd.h, which is reported as unused by clangd.  Add
cli/cli-cmds.h instead, to get access to `cmdlist` and friends.

Change-Id: Ic0c60d2f6d3618f1bd9fd80b95ffd7c33c692a04

gdb/infrun.c

diff --git a/gdb/infrun.c b/gdb/infrun.c
index a5030b1..d23be9e 100644
--- a/gdb/infrun.c
+++ b/gdb/infrun.c
@@ -18,6 +18,7 @@
    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
+#include "cli/cli-cmds.h"
 #include "displaced-stepping.h"
 #include "infrun.h"
 #include <ctype.h>
@@ -26,7 +27,6 @@
 #include "inferior.h"
 #include "breakpoint.h"
 #include "gdbcore.h"
-#include "gdbcmd.h"
 #include "target.h"
 #include "target-connection.h"
 #include "gdbthread.h"