cmake: Fix Ninja multiple rules error

Currently "cmake -G Ninja" complains about "multiple rules generate
src/libssh_dev.map", because the target has the same name as the output
of the custom command.

Signed-off-by: DDoSolitary <DDoSolitary@gmail.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>

cmake/Modules/FindABIMap.cmake

@@ -469,12 +469,12 @@ function(generate_map_file _TARGET_NAME)
     # a generated source
     add_custom_command(
         OUTPUT ${_MAP_OUTPUT_PATH}
-        DEPENDS ${_TARGET_NAME}
+        DEPENDS ${_TARGET_NAME}_copy
     )
 
     if (DEFINED _generate_map_file_COPY_TO)
         # Copy the generated map back to the COPY_TO
-        add_custom_target(${_TARGET_NAME} ALL
+        add_custom_target(${_TARGET_NAME}_copy ALL
             COMMAND
               ${CMAKE_COMMAND} -E copy_if_different ${_MAP_OUTPUT_PATH}
               ${_generate_map_file_COPY_TO}
@@ -483,7 +483,7 @@ function(generate_map_file _TARGET_NAME)
             VERBATIM
         )
     else()
-        add_custom_target(${_TARGET_NAME} ALL
+        add_custom_target(${_TARGET_NAME}_copy ALL
             DEPENDS ${_TARGET_NAME}_int
         )
     endif()