Let it compile when pmix is not found (#185)

cmake/find_pmix.cmake

@@ -57,6 +57,6 @@ macro(check_pmix)
   if (PMIX_HEADER AND PMIX_LIBRARY)
     set(PMIX_INCLUDE_DIRECTORIES ${PMIX_HEADER})
     set(PMIX_LIBRARIES ${PMIX_LIBRARY})
-    set(HAVE_PMIX TRUE)
+    set(PMIx_FOUND TRUE)
   endif()
 endmacro()

tests/functional_tests/CMakeLists.txt

@@ -90,7 +90,7 @@ endif()
 target_compile_definitions(
   ${PROJECT_NAME}
   PRIVATE
-    $<$<BOOL:HAVE_PMIX>:HAVE_PMIX=1>
+    $<$<BOOL:${PMIx_FOUND}>:HAVE_PMIX=1>
 )
 
 target_include_directories(