sh: Fix compilation warning in do_pipe due to missing prototype

* defs.h [SH]: Make getrval2 prototype visible to do_pipe
and fix the following compiler warning:
.../net.c: In function 'do_pipe':
.../net.c:1632: warning: implicit declaration of function 'getrval2'
.../net.c:1632: warning: format '%lu' expects type 'long unsigned int',
but argument 3 has type 'int'

Signed-off-by: Carmelo Amoroso <carmelo.amoroso@st.com>
1 file changed