tools: bpftool: Fix minor bash completion mistakes

Minor fixes for bash completion: addition of program name completion for
two subcommands, and correction for program test-runs and map pinning.

The completion for the following commands is fixed or improved:

    # bpftool prog run [TAB]
    # bpftool prog pin [TAB]
    # bpftool map pin [TAB]
    # bpftool net attach xdp name [TAB]

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200312184608.12050-3-quentin@isovalent.com

tools/bpf/bpftool/bash-completion/bpftool

@@ -542,8 +542,8 @@ _bpftool()
                     esac
                     ;;
                 run)
-                    if [[ ${#words[@]} -lt 5 ]]; then
-                        _filedir
+                    if [[ ${#words[@]} -eq 4 ]]; then
+                        COMPREPLY=( $( compgen -W "$PROG_TYPE" -- "$cur" ) )
                         return 0
                     fi
                     case $prev in
@@ -551,6 +551,10 @@ _bpftool()
                             _bpftool_get_prog_ids
                             return 0
                             ;;
+                        name)
+                            _bpftool_get_prog_names
+                            return 0
+                            ;;
                         data_in|data_out|ctx_in|ctx_out)
                             _filedir
                             return 0
@@ -756,11 +760,17 @@ _bpftool()
                     esac
                     ;;
                 pin)
-                    if [[ $prev == "$command" ]]; then
-                        COMPREPLY=( $( compgen -W "$PROG_TYPE" -- "$cur" ) )
-                    else
-                        _filedir
-                    fi
+                    case $prev in
+                        $command)
+                            COMPREPLY=( $( compgen -W "$MAP_TYPE" -- "$cur" ) )
+                            ;;
+                        id)
+                            _bpftool_get_map_ids
+                            ;;
+                        name)
+                            _bpftool_get_map_names
+                            ;;
+                    esac
                     return 0
                     ;;
                 event_pipe)
@@ -887,7 +897,7 @@ _bpftool()
             case $command in
                 skeleton)
                     _filedir
-		    ;;
+                    ;;
                 *)
                     [[ $prev == $object ]] && \
                         COMPREPLY=( $( compgen -W 'skeleton help' -- "$cur" ) )
@@ -987,6 +997,9 @@ _bpftool()
                                 id)
                                     _bpftool_get_prog_ids
                                     ;;
+                                name)
+                                    _bpftool_get_prog_names
+                                    ;;
                                 pinned)
                                     _filedir
                                     ;;