bash-completion: get rid of "have" calls

have function disappeared in bash-completion 1.90 (2011)

src/util/bash-completion/mdb-export

@@ -1,5 +1,4 @@
 #-*- mode: shell-script;-*-
-have mdb-export &&
 _mdb_export()
 {
 	local cur prev

src/util/bash-completion/mdb-hexdump

@@ -1,5 +1,4 @@
 #-*- mode: shell-script;-*-
-have mdb-hexdump &&
 _mdb_hexdump()
 {
 	local cur

src/util/bash-completion/mdb-import

@@ -1,5 +1,4 @@
 #-*- mode: shell-script;-*-
-have mdb-import &&
 _mdb_import()
 {
 	local cur

src/util/bash-completion/mdb-parsecsv

@@ -1,5 +1,4 @@
 #-*- mode: shell-script;-*-
-have mdb-parsecsv &&
 _mdb_parsecsv()
 {
 	local cur

src/util/bash-completion/mdb-prop

@@ -1,5 +1,4 @@
 #-*- mode: shell-script;-*-
-have mdb-prop &&
 _mdb_prop()
 {
 	local cur

src/util/bash-completion/mdb-schema

@@ -1,5 +1,4 @@
 #-*- mode: shell-script;-*-
-have mdb-schema &&
 _mdb_schema()
 {
 	local cur prev

src/util/bash-completion/mdb-sql

@@ -1,5 +1,4 @@
 #-*- mode: shell-script;-*-
-have mdb-sql &&
 _mdb_sql()
 {
 	local cur prev

src/util/bash-completion/mdb-tables

@@ -1,5 +1,4 @@
 #-*- mode: shell-script;-*-
-have mdb-tables &&
 _mdb_tables()
 {
 	local cur prev

src/util/bash-completion/mdb-ver

@@ -1,5 +1,4 @@
 #-*- mode: shell-script;-*-
-have mdb-ver &&
 _mdb_ver()
 {
 	local cur