vulkan: fix memory leaks on error
commit 1096f02dc12d77ee4eb1642a689b0c12543ab2fd Author: Stéphane Cerveau scerveau@igalia.com Date: Fri May 31 12:28:40 2024 +0200
vkutils: do not forget to clear context in case of error
The context is leaking in case of a failing instance open.
commit a01513ad415afe162c06f7160a3c3c15f36ee6e6 Author: Stéphane Cerveau scerveau@igalia.com Date: Fri May 31 12:27:30 2024 +0200
vkerror: free the error string after usage
g_set_error already used the var string, can clear it now.