bpftool: Clean up _bpftool_once_attr() calls in bash completion

In bpftool's bash completion file, function _bpftool_once_attr() is able
to process multiple arguments. There are a few locations where this
function is called multiple times in a row, each time for a single
argument; let's pass all arguments instead to minimize the number of
function calls required for the completion.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20230405132120.59886-8-quentin@isovalent.comSigned-off-by: Alexei Starovoitov <ast@kernel.org>

tools/bpf/bpftool/bash-completion/bpftool

@@ -508,10 +508,7 @@ _bpftool()
                             ;;
                         *)
                             COMPREPLY=( $( compgen -W "map" -- "$cur" ) )
-                            _bpftool_once_attr 'type'
-                            _bpftool_once_attr 'dev'
-                            _bpftool_once_attr 'pinmaps'
-                            _bpftool_once_attr 'autoattach'
+                            _bpftool_once_attr 'type dev pinmaps autoattach'
                             return 0
                             ;;
                     esac
@@ -736,16 +733,10 @@ _bpftool()
                             esac
                             ;;
                         *)
-                            _bpftool_once_attr 'type'
-                            _bpftool_once_attr 'key'
-                            _bpftool_once_attr 'value'
-                            _bpftool_once_attr 'entries'
-                            _bpftool_once_attr 'name'
-                            _bpftool_once_attr 'flags'
+                            _bpftool_once_attr 'type key value entries name flags dev'
                             if _bpftool_search_list 'array_of_maps' 'hash_of_maps'; then
                                 _bpftool_once_attr 'inner_map'
                             fi
-                            _bpftool_once_attr 'dev'
                             return 0
                             ;;
                     esac
@@ -886,8 +877,7 @@ _bpftool()
                             return 0
                             ;;
                         *)
-                            _bpftool_once_attr 'cpu'
-                            _bpftool_once_attr 'index'
+                            _bpftool_once_attr 'cpu index'
                             return 0
                             ;;
                     esac