tiny-printf: Add support for %p format

tiny-printf: Add support for %p format

Add support for %p, %pa[p], %pM, %pm and %pI4 formats to tiny-printf.
%pM and %pI4 are widely used by SPL networking stack and is required if
networking support is desired in SPL.
%p, %pa and %pap are mostly used by debug prints and hence supported
only when DEBUG is enabled.

Before this patch:
$ size spl/u-boot-spl
   text	   data	    bss	    dec	    hex	filename
  99325	   4899	 218584	 322808	  4ecf8	spl/u-boot-spl

After this patch (with CONFIG_SPL_NET_SUPPORT):
$ size spl/u-boot-spl
   text	   data	    bss	    dec	    hex	filename
  99666	   4899	 218584	 323149	  4ee4d	spl/u-boot-spl

So, this patch adds ~350 bytes to code size.

If CONFIG_SPL_NET_SUPPORT is not enabled, this adds ~25 bytes.

If CONFIG_USE_TINY_PRINTF is disabled then:
$ size spl/u-boot-spl
  text	   data	    bss	    dec	    hex	filename
 101116	   4899	 218584	 324599	  4f3f7	spl/u-boot-spl

So, there is still ~1.4K space saved even with support for %pM/%pI4.

Compiler used is to build is:
arm-linux-gnueabihf-gcc (Linaro GCC 6.2-2016.11) 6.2.1 20161016

Signed-off-by: Vignesh R <vigneshr@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>