[Bug c++/99166] New: [modules] Unable to determine where CMI is being found

[nathan at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99166

            Bug ID: 99166
           Summary: [modules] Unable to determine where CMI is being found
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: nathan at gcc dot gnu.org
  Target Milestone: ---

If a CMI file is not found one gets a diagnostic saying where it was looking. 
For include translation -flang-info-include-translate and friends are there to
inform.  But there is no information when the compiler reads a found CMI, which
can be confusing to build system debugging.  

Add -flang-info-module-cmi and friends in a similar vein to the
include-translate informs