[lldb][cmake] Create dependencies for LLDB header targets (llvm#150995)

The LLDB standalone build using Xcode currently fails due to the headers
being attached to multiple targets, but none of these targets depending
on each other. This commit resolves this by creating those dependencies.

(cherry picked from commit c162846)

Author: chelcassanova

lldb/source/API/CMakeLists.txt

@@ -360,6 +360,9 @@ foreach(header
     set(copy_command ${CMAKE_COMMAND} -E copy ${header} ${staged_header})
   endif()
 
+  add_custom_target(liblldb-stage-header-${basename} DEPENDS ${staged_header})
+  add_dependencies(liblldb-stage-header-${basename} lldb-sbapi-dwarf-enums)
+  add_dependencies(liblldb-header-staging liblldb-stage-header-${basename})
   add_custom_command(
     DEPENDS ${header} OUTPUT ${staged_header}
     COMMAND ${copy_command}
@@ -371,6 +374,7 @@ foreach(header
     set(output_header $<TARGET_FILE_DIR:liblldb>/Headers/${basename})
 
     add_custom_target(lldb-framework-fixup-header-${basename} DEPENDS ${staged_header})
+    add_dependencies(lldb-framework-fixup-header-${basename} liblldb-stage-header-${basename})
     add_dependencies(lldb-framework-fixup-all-headers lldb-framework-fixup-header-${basename})
 
     add_custom_command(TARGET lldb-framework-fixup-header-${basename} POST_BUILD