x86: zimage: Remove acpi_rsdp_addr propagation to kernel boot parameters

x86: zimage: Remove acpi_rsdp_addr propagation to kernel boot parameters

As of today, the proposal of adding "acpi_rsdp_addr" to the kernel
boot protocol does not make its way to the kernel mainline. This
creates some confusion if we leave it in the U-Boot code base.
Remove it for now until we have a clear picture with kernel upstream.

Note this eventually does a partial revert to commit 3469bf427454
("x86: zImage: Propagate acpi_rsdp_addr to kernel via boot parameters")

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Simon Glass <sjg@chromium.org>