inel-mpi: fix for wrong structure name instroduced in ea8a0be4 (#17382)

it's    mpi_compiler_wrappers
and not mpi_compiler._wrappers

fixes 2nd part of #17371

var/spack/repos/builtin/packages/intel-mpi/package.py

@@ -67,5 +67,5 @@ def setup_dependent_build_environment(self, *args):
     def setup_run_environment(self, env):
         super(IntelMpi, self).setup_run_environment(env)
 
-        for name, value in self.mpi_compiler.wrappers.items():
+        for name, value in self.mpi_compiler_wrappers.items():
             env.set(name, value)