papi fortran: Add support for papif_get_component_index

[Treece-Burgess]

Pull Request Description

This PR adds support for PAPI_get_component_index in the PAPI Fortran interface.

Testing

Testing was done on Picard at Oregon (OS: RHEL 8.10 , CPU: Intel Xeon Gold 6430).

I modified ftests/eventname.F, to be as follows:

#include "fpapi.h"

      program component_index
      INTEGER retval, cidx

      retval = PAPI_VER_CURRENT
      call PAPIf_library_init( retval )
      if (retval.NE.PAPI_VER_CURRENT) then
          print *, "Call to PAPIf_library_init failed."
          call exit(1)
      end if

      call PAPIf_get_component_index( "sysdetect", cidx )
      if (cidx.LT.0) then
          print *, "Call to PAPIf_get_component_index failed."
          call exit(1)
      end if
      write (*, 1) cidx
  1   format ("Call 1: The sysdetect component index is: ", Z10)

      call papif_get_component_index( "sysdetect", cidx )
      if (cidx.LT.0) then
          print *, "Call to papif_get_component_index failed."
          call exit(1)
      end if 
      write (*, 2) cidx
  2   format ("Call 2: The sysdetect component index is: ", Z10)

      end 

As I am on Linux, I always enter the if defined(_FORTRAN_STRLEN_AT_END) block of code. Therefore, to test the else block I changed if defined(_FORTRAN_STRLEN_AT_END) to if 0. You then will need to use iso_c_binding and null terminate the string. Otherwise, junk will be placed at the end of the string.

Author Checklist

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