Fix a warning from MSVC build

Apparently after internal/numbers.h defines INTx_MIN/MAX
stdint gets included and it defines those differently:

C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\INCLUDE\stdint.h(48):
 warning C4005: 'INT8_MIN': macro redefinition

Avoid that by changing the sequence in which the include files
appear in crypto/bio/b_print.c.

[extended tests]

Reviewed-by: Tim Hudson <tjh@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6995)