MIPS: Remove obsolete MIPS checks for DST node "chosen@0"

As there is precious little left in any DTS files referring to the
node "/chosen@0" as opposed to "/chosen", remove the two checks for
the former node name.

[paul.burton@mips.com:
  The modified yamon-dt code only operates on
  arch/mips/boot/dts/mti/sead3.dts right now, and that uses chosen
  rather than chosen@0 anyway, so this should have no behavioural
  effect.]
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/20131/
Cc: linux-mips@linux-mips.org

arch/mips/generic/yamon-dt.c

@@ -27,8 +27,6 @@ __init int yamon_dt_append_cmdline(void *fdt)
 
 	/* find or add chosen node */
 	chosen_off = fdt_path_offset(fdt, "/chosen");
-	if (chosen_off == -FDT_ERR_NOTFOUND)
-		chosen_off = fdt_path_offset(fdt, "/chosen@0");
 	if (chosen_off == -FDT_ERR_NOTFOUND)
 		chosen_off = fdt_add_subnode(fdt, 0, "chosen");
 	if (chosen_off < 0) {
@@ -220,8 +218,6 @@ __init int yamon_dt_serial_config(void *fdt)
 
 	/* find or add chosen node */
 	chosen_off = fdt_path_offset(fdt, "/chosen");
-	if (chosen_off == -FDT_ERR_NOTFOUND)
-		chosen_off = fdt_path_offset(fdt, "/chosen@0");
 	if (chosen_off == -FDT_ERR_NOTFOUND)
 		chosen_off = fdt_add_subnode(fdt, 0, "chosen");
 	if (chosen_off < 0) {