armv8/fsl-layerscape: fdt: avoid incorrect fixing with CONFIG_SYS_CLK_FREQ

Current sysclk fixing would fix all clocks with 'fixed-clock' compatible.
This patch is to fix sysclk by path to avoid any incorrect fixing.

Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Reviewed-by: York Sun <york.sun@nxp.com>
diff --git a/arch/arm/cpu/armv8/fsl-layerscape/fdt.c b/arch/arm/cpu/armv8/fsl-layerscape/fdt.c
index 762a95b..05c4577 100644
--- a/arch/arm/cpu/armv8/fsl-layerscape/fdt.c
+++ b/arch/arm/cpu/armv8/fsl-layerscape/fdt.c
@@ -373,8 +373,8 @@
 			       "clock-frequency", CONFIG_SYS_NS16550_CLK, 1);
 #endif
 
-	do_fixup_by_compat_u32(blob, "fixed-clock",
-			       "clock-frequency", CONFIG_SYS_CLK_FREQ, 1);
+	do_fixup_by_path_u32(blob, "/sysclk", "clock-frequency",
+			     CONFIG_SYS_CLK_FREQ, 1);
 
 #ifdef CONFIG_PCI
 	ft_pci_setup(blob, bd);