GetPrerequisites: Update output matching for newer 'file' versions

Detect PIE binaries with newer 'file' (5.22).  It no longer prints
"(uses shared libraries)" but does print "interpreter":

 # file 5.19
 $ file /usr/bin/su
 /usr/bin/su: ... shared object, ..., dynamically linked (uses shared libs), ...

 # file 5.22
 $ file /usr/bin/su
 /usr/bin/su: ... shared object, ..., dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, ...

Modules/GetPrerequisites.cmake

@@ -260,6 +260,13 @@ function(is_file_executable file result_var)
         return()
       endif()
 
+      # "file" version 5.22 does not print "(used shared libraries)"
+      # but uses "interpreter"
+      if("${file_ov}" MATCHES "shared object.*interpreter")
+        set(${result_var} 1 PARENT_SCOPE)
+        return()
+      endif()
+
     else()
       message(STATUS "warning: No 'file' command, skipping execute_process...")
     endif()