xen/arm: domain_build: Remove redundant check in make_vpl011_uart_node()

None of the code since the last check of res modify the value. So the
check can be removed.

Coverity-ID: 1476824
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>

xen/arch/arm/domain_build.c

@@ -1661,8 +1661,7 @@ static int __init make_vpl011_uart_node(const struct domain *d, void *fdt)
     dt_child_set_range(&cells, GUEST_ROOT_ADDRESS_CELLS,
                        GUEST_ROOT_SIZE_CELLS, GUEST_PL011_BASE,
                        GUEST_PL011_SIZE);
-    if ( res )
-        return res;
+
     res = fdt_property(fdt, "reg", reg, sizeof(reg));
     if ( res )
         return res;