Fix installation of base soname for libraries with release number in the name.

This resolves regression from prior commit.

Signed-off-by: Slávek Banko <slavek.banko@axis.cz>
(cherry picked from commit ab096402b3)

modules/TDEMacros.cmake

@@ -884,7 +884,7 @@ macro( tde_add_library _arg_target )
 
     # install base soname
     if( _release AND NOT "STATIC" STREQUAL ${_type} )
-      tde_get_library_filename( _output ${_target} )
+      tde_get_library_filename( _soname ${_target} )
       string( REPLACE "-${_release}" "" _soname_base "${_soname}" )
       if( _version )
         get_target_property( _soversion ${_target} SOVERSION )