configs: rename phoneprov_users.conf to .sample so make installs it

This conf file should be suffixed .sample so that make installs it
at compile time. Otherwise res_phoneprov complains at runtime as to
its absence and refuses to start.

Fixes: #1626

configs/samples/phoneprov_users.conf.sample

@@ -0,0 +1,40 @@
+;
+; Device provisioning configuration
+;
+; This file is used by res_phoneprov to define provisioning entries.
+;
+
+[general]
+;
+; Full name of a user
+;
+fullname = New User
+;
+; MAC Address for res_phoneprov
+;
+;macaddress = 112233445566
+;
+; Auto provision the phone with res_phoneprov
+;
+;autoprov = yes
+;
+; Line Keys for hardphone
+;
+;LINEKEYS = 1
+;
+; Line number for hardphone
+;
+;linenumber = 1
+;
+; Local Caller ID number used with res_phoneprov and Asterisk GUI
+;
+;cid_number = 6000
+
+;[6000]
+;fullname = Joe User
+;secret = 1234
+;macaddress = 112233445566
+;autoprov = yes
+;LINEKEYS = 1
+;linenumber = 1
+;cid_number = 6000