* lib/gdb.exp (gdb_skip_float_test): New proc. Skip test if
no floating point support.
(gdb_skip_stdio_test): New proc. Skip test if no stdio support.
* gdb.base/call-ar-st.exp: Use above procs to skip tests.
* gdb.base/call-rt-st.exp: Ditto.
* gdb.base/call-strs.exp: Ditto.
* gdb.base/sizeof.exp (check_sizeof): Skip if no printf support.
* gdb.base/varargs.exp: Skip entire test if no printf support.
* gdb.base/ending-run.exp (Step to return): Skip if no printf supt.
* gdb.base/shlib-call.exp: Skip several tests if no printf support.
* gdb.base/miscexprs.exp: make sizeof long array test portable.
* gdb.base/ending-run.exp: After connecting to a remote target,
but before running, the target will appear to be in a random
location. Specify both a file and a line for breakpoints.
Also, the function that calls main may be called 'init'
rather than 'start'.