Inline a better version of print_bin() in only caller

Inline a better version of print_bin() in only caller

Instead of printing to a temporary buffer with weird gymnastics, we can
simply write things out to the BIO using proper indent. This still isn't
perfect since we have a CBS version of this in ecx_buf_print(), which is
basically what used to be ASN1_buf_print(). Annotate this with an XXX for
future cleanup.

ok beck