CMake: Ensure abc executable depends on libabc

This ensures that libabc is built only once.

Previously the code for libabc was being built twice: once for the
abc executable target, and again for the libabc target.

CMakeLists.txt

@@ -88,15 +88,17 @@ function(abc_properties target visibility)
     target_link_libraries(${target} ${visibility} ${ABC_LIBS})
 endfunction()
 
-add_executable(abc ${ABC_SRC})
-abc_properties(abc PRIVATE)
-
-list(REMOVE_ITEM ABC_SRC src/base/main/main.c)
+set(ABC_MAIN_SRC src/base/main/main.c)
+list(REMOVE_ITEM ABC_SRC ${ABC_MAIN_SRC})
 
 add_library(libabc EXCLUDE_FROM_ALL ${ABC_SRC})
 abc_properties(libabc PUBLIC)
 set_property(TARGET libabc PROPERTY OUTPUT_NAME abc)
 
+add_executable(abc ${ABC_MAIN_SRC})
+target_link_libraries(abc PRIVATE libabc)
+abc_properties(abc PRIVATE)
+
 add_library(libabc-pic EXCLUDE_FROM_ALL ${ABC_SRC})
 abc_properties(libabc-pic PUBLIC)
 set_property(TARGET libabc-pic PROPERTY POSITION_INDEPENDENT_CODE ON)