[pygobject] pygi_arg_cache_alloc() never returns NULL

[Christoph Reiter <creiter src gnome org>]

commit ed8538d8b7de45050d931edd036853944ff04d47
Author: Christoph Reiter <reiter christoph gmail com>
Date:   Thu Mar 29 22:02:36 2018 +0200

    pygi_arg_cache_alloc() never returns NULL

 gi/pygi-basictype.c | 2 --
 gi/pygi-error.c     | 4 +---
 2 files changed, 1 insertion(+), 5 deletions(-)
---
diff --git a/gi/pygi-basictype.c b/gi/pygi-basictype.c
index 05080306..27966bfe 100644
--- a/gi/pygi-basictype.c
+++ b/gi/pygi-basictype.c
@@ -1062,8 +1062,6 @@ pygi_arg_basic_type_new_from_info (GITypeInfo   *type_info,
 {
     gboolean res = FALSE;
     PyGIArgCache *arg_cache = pygi_arg_cache_alloc ();
-    if (arg_cache == NULL)
-        return NULL;
 
     res = arg_basic_type_setup_from_info (arg_cache,
                                           type_info,
diff --git a/gi/pygi-error.c b/gi/pygi-error.c
index 4feefc4b..18c488a0 100644
--- a/gi/pygi-error.c
+++ b/gi/pygi-error.c
@@ -328,11 +328,9 @@ pygi_arg_gerror_new_from_info (GITypeInfo   *type_info,
                                PyGIDirection direction)
 {
     gboolean res = FALSE;
-    PyGIArgCache *arg_cache = NULL;
+    PyGIArgCache *arg_cache;
 
     arg_cache = pygi_arg_cache_alloc ();
-    if (arg_cache == NULL)
-        return NULL;
 
     res = pygi_arg_gerror_setup_from_info (arg_cache,
                                            type_info,