test-ls: discover socket mode like symlink mode

This addresses the single failed test under Cygwin. Tested on both a
new Cygwin64 installation and (Fedora) Linux.

On Cygwin64 the full mode is "srw-------" rather than "srwx------".

Signed-off-by: Paul Kronenwetter <kronenpj@gmail.com>
[rlb@defaultvalue.org: adjust commit message]
Reviewed-by: Rob Browning <rlb@defaultvalue.org>
Tested-by: Rob Browning <rlb@defaultvalue.org>

t/test-ls.sh

@@ -132,6 +132,7 @@ d--------- ?/? 0 1970-01-01 00:00 .tag/
 d--------- ?/? 0 1970-01-01 00:00 src/"
 
 symlink_mode="$(WVPASS ls -l src/symlink | cut -b -10)" || exit $?
+socket_mode="$(WVPASS ls -l src/socket | cut -b -10)" || exit $?
 
 symlink_bup_info="$(WVPASS bup ls -l src/latest"$tmpdir"/src | grep symlink)" \
     || exit $?
@@ -159,7 +160,7 @@ WVPASSEQ "$(bup ls -l src/latest"$tmpdir"/src | tr -s ' ' ' ')" \
 "-rwx------ $user/$group 0 2009-10-03 23:48 executable
 prw------- $user/$group 0 2009-10-03 23:48 fifo
 -rw------- $user/$group 1024 2009-10-03 23:48 file
-srwx------ $user/$group 0 2009-10-03 23:48 socket
+$socket_mode $user/$group 0 2009-10-03 23:48 socket
 $symlink_mode $user/$group $symlink_size $symlink_date symlink -> file"
 
 WVPASSEQ "$(bup ls -la src/latest"$tmpdir"/src | tr -s ' ' ' ')" \
@@ -169,36 +170,36 @@ drwx------ $user/$group 0 2009-10-03 23:48 ..
 -rwx------ $user/$group 0 2009-10-03 23:48 executable
 prw------- $user/$group 0 2009-10-03 23:48 fifo
 -rw------- $user/$group 1024 2009-10-03 23:48 file
-srwx------ $user/$group 0 2009-10-03 23:48 socket
+$socket_mode $user/$group 0 2009-10-03 23:48 socket
 $symlink_mode $user/$group $symlink_size $symlink_date symlink -> file"
 
 WVPASSEQ "$(bup ls -lA src/latest"$tmpdir"/src | tr -s ' ' ' ')" \
 "-rw------- $user/$group 0 2009-10-03 23:48 .dotfile
 -rwx------ $user/$group 0 2009-10-03 23:48 executable
 prw------- $user/$group 0 2009-10-03 23:48 fifo
 -rw------- $user/$group 1024 2009-10-03 23:48 file
-srwx------ $user/$group 0 2009-10-03 23:48 socket
+$socket_mode $user/$group 0 2009-10-03 23:48 socket
 $symlink_mode $user/$group $symlink_size $symlink_date symlink -> file"
 
 WVPASSEQ "$(bup ls -lF src/latest"$tmpdir"/src | tr -s ' ' ' ')" \
 "-rwx------ $user/$group 0 2009-10-03 23:48 executable*
 prw------- $user/$group 0 2009-10-03 23:48 fifo|
 -rw------- $user/$group 1024 2009-10-03 23:48 file
-srwx------ $user/$group 0 2009-10-03 23:48 socket=
+$socket_mode $user/$group 0 2009-10-03 23:48 socket=
 $symlink_mode $user/$group $symlink_size $symlink_date symlink@ -> file"
 
 WVPASSEQ "$(bup ls -l --file-type src/latest"$tmpdir"/src | tr -s ' ' ' ')" \
 "-rwx------ $user/$group 0 2009-10-03 23:48 executable
 prw------- $user/$group 0 2009-10-03 23:48 fifo|
 -rw------- $user/$group 1024 2009-10-03 23:48 file
-srwx------ $user/$group 0 2009-10-03 23:48 socket=
+$socket_mode $user/$group 0 2009-10-03 23:48 socket=
 $symlink_mode $user/$group $symlink_size $symlink_date symlink@ -> file"
 
 WVPASSEQ "$(bup ls -ln src/latest"$tmpdir"/src | tr -s ' ' ' ')" \
 "-rwx------ $uid/$gid 0 2009-10-03 23:48 executable
 prw------- $uid/$gid 0 2009-10-03 23:48 fifo
 -rw------- $uid/$gid 1024 2009-10-03 23:48 file
-srwx------ $uid/$gid 0 2009-10-03 23:48 socket
+$socket_mode $uid/$gid 0 2009-10-03 23:48 socket
 $symlink_mode $uid/$gid $symlink_size $symlink_date symlink -> file"
 
 WVPASSEQ "$(bup ls -ld "src/latest$tmpdir/src" | tr -s ' ' ' ')" \
@@ -220,7 +221,7 @@ WVPASSEQ "$(bup ls -ln src/latest"$tmpdir"/src | tr -s ' ' ' ')" \
 "-rwx------ $uid/$gid 0 2009-10-03 18:48 executable
 prw------- $uid/$gid 0 2009-10-03 18:48 fifo
 -rw------- $uid/$gid 1024 2009-10-03 18:48 file
-srwx------ $uid/$gid 0 2009-10-03 18:48 socket
+$socket_mode $uid/$gid 0 2009-10-03 18:48 socket
 $symlink_mode $uid/$gid $symlink_size $symlink_date_central symlink -> file"
 unset TZ