powerpc/512x: Constify clk_div_tables

clk_div_tables are not supposed to change at runtime.
mpc512x_clk_divtable function working with const clk_div_table. So
mark the non-const structs as const.
Signed-off-by: NArvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

arch/powerpc/platforms/512x/clock-commonclk.c

@@ -363,7 +363,7 @@ static int get_cpmf_mult_x2(void)
  */
 
 /* applies to the IPS_DIV, and PCI_DIV values */
-static struct clk_div_table divtab_2346[] = {
+static const struct clk_div_table divtab_2346[] = {
 	{ .val = 2, .div = 2, },
 	{ .val = 3, .div = 3, },
 	{ .val = 4, .div = 4, },
@@ -372,7 +372,7 @@ static struct clk_div_table divtab_2346[] = {
 };
 
 /* applies to the MBX_DIV, LPC_DIV, and NFC_DIV values */
-static struct clk_div_table divtab_1234[] = {
+static const struct clk_div_table divtab_1234[] = {
 	{ .val = 1, .div = 1, },
 	{ .val = 2, .div = 2, },
 	{ .val = 3, .div = 3, },