i965: use strtol to convert the integer deviceID override

One can override the deviceID, by setting the INTEL_DEVID_OVERRIDE
variable. A few symbolic names or a numerical value for the actual
device ID is accepted.

At the same time we're using strtod (string to double) to convert the
string to a decimal numeral. A seeming thinko, made by the original
commit that introduces the code in libdrm_intel and got here with the
import.

Fixes: 514db96c11 ("i965: Import libdrm_intel.")
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>

src/mesa/drivers/dri/i965/intel_screen.c

@@ -2028,7 +2028,7 @@ parse_devid_override(const char *devid_override)
          return name_map[i].pci_id;
    }
 
-   return strtod(devid_override, NULL);
+   return strtol(devid_override, NULL, 0);
 }
 
 /**