testsuite: add the req_process predicate

This patch adds the req_process predicate to the testsuite to assert
the platform has a process model, also marking tests that involve
spawning processes as req_process. Also bumps hpc & process submodule.

(cherry picked from commit ce580426)

testsuite/driver/testglobals.py

@@ -134,6 +134,8 @@ class TestConfig:
         # Do we have interpreter support?
         self.have_interp = False
 
+        # Do we even have processes?
+        self.have_process = True
         # Does the platform support loading of dynamic shared libraries? e.g.
         # some musl-based environments do not.
         self.supports_dynamic_libs = True

testsuite/driver/testlib.py

@@ -274,6 +274,9 @@ def req_smp( name, opts ):
     if not config.have_smp:
         opts.expect = 'fail'
 
+def req_process( name, opts ):
+    if not config.have_process:
+        opts.skip = True
 def ignore_stdout(name, opts):
     opts.ignore_stdout = True