Use the source keyword at allocation instead of the loct_pointer module

Description

Replace the use of the loct_pointer_copy and loct_allocatable_copy routines with new SAFE_ALLOCATE_SOURCE macros. These macros uses the source keyword of the allocate statement. As a bonus, the profiler should now correctly account memory allocated this way.

News snippet

Replace the use of the loct_pointer_copy and loct_allocatable_copy with new SAFE_ALLOCATE_SOURCE macros.

Checklist

• I have checked that my code follows the Octopus coding standards
• I have added tests for all the new features added in this request.