virPCIDeviceBindToStub: Remove unused @oldDriverPath and @oldDriverName

These two chunks had to be part of df4283a5. But for some unclear
reason, the weren't. Anyway, these two variables are not used anywhere
within function. They're initialized to NULL and then VIR_FREE()-d. And
there's no reason do do two NOPs, right?
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

src/util/virpci.c

@@ -1085,8 +1085,6 @@ virPCIDeviceBindToStub(virPCIDevicePtr dev,
 
     char *stubDriverPath = NULL;
     char *driverLink = NULL;
-    char *oldDriverPath = NULL;
-    char *oldDriverName = NULL;
     char *path = NULL; /* reused for different purposes */
     const char *newDriverName = NULL;
 
@@ -1217,8 +1215,6 @@ remove_id:
 cleanup:
     VIR_FREE(stubDriverPath);
     VIR_FREE(driverLink);
-    VIR_FREE(oldDriverPath);
-    VIR_FREE(oldDriverName);
     VIR_FREE(path);
 
     if (newDriverName &&