fix default case to include all components in the package

cmake/opentelemetry-cpp-config.cmake.in

@@ -158,9 +158,20 @@ set(_OPENTELEMETRY_CPP_TARGETS
 
 set(_FIND_ALL_COMPONENTS TRUE)
 
+set(_OPENTELEMETRY_CPP_REQUESTED_COMPONENTS)
+
 if(NOT DEFINED opentelemetry-cpp_FIND_COMPONENTS OR opentelemetry-cpp_FIND_COMPONENTS STREQUAL "")
   # if no components are requested then find all installed components
-  set(_OPENTELEMETRY_CPP_REQUESTED_COMPONENTS ${_OPENTELEMETRY_CPP_COMPONENTS})
+
+  set(_TARGET_FILES_DIR "${CMAKE_CURRENT_LIST_DIR}")
+
+  foreach(_COMPONENT IN LISTS _OPENTELEMETRY_CPP_COMPONENTS)
+      set(_COMPONENT_TARGET_FILE "${_TARGET_FILES_DIR}/opentelemetry-cpp-${_COMPONENT}-target.cmake")
+      if(EXISTS "${_COMPONENT_TARGET_FILE}")
+          list(APPEND _OPENTELEMETRY_CPP_REQUESTED_COMPONENTS ${_COMPONENT})
+      endif()
+  endforeach()
+
 else()
   set(_FIND_ALL_COMPONENTS FALSE)
   # check that the requested components are valid and installed