meson: simplify add_project_arguments for OEM_IBM

Set it in one line for both C and C++.

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I40cba5500a92b66ec0fe1dea935a5ce5da0a3a38
diff --git a/meson.build b/meson.build
index 3430735..0576048 100644
--- a/meson.build
+++ b/meson.build
@@ -56,8 +56,7 @@
   conf_data.set_quoted('LID_RUNNING_PATCH_DIR', '/usr/local/share/hostfw/running')
   conf_data.set_quoted('LID_ALTERNATE_PATCH_DIR', '/usr/local/share/hostfw/alternate')
   conf_data.set('DMA_MAXSIZE', get_option('oem-ibm-dma-maxsize'))
-  add_project_arguments('-DOEM_IBM', language : 'c')
-  add_project_arguments('-DOEM_IBM', language : 'cpp')
+  add_project_arguments('-DOEM_IBM', language : ['c', 'cpp'])
 endif
 conf_data.set('NUMBER_OF_REQUEST_RETRIES', get_option('number-of-request-retries'))
 conf_data.set('INSTANCE_ID_EXPIRATION_INTERVAL',get_option('instance-id-expiration-interval'))