re PR testsuite/36285 (gcc.dg/compat/struct-by-value-xxx improper test for AVR target)

re PR testsuite/36285 (gcc.dg/compat/struct-by-value-xxx improper test for AVR target)

PR testsuite/36285
* gcc.dg/compat/struct-by-value-16_x.c: Move some tests to new file to reduce code size.
* gcc.dg/compat/struct-by-value-16_y.c: Ditto.
* gcc.dg/compat/struct-by-value-16a_main.c: New file.
* gcc.dg/compat/struct-by-value-16a_x.c: Ditto.
* gcc.dg/compat/struct-by-value-16a_y.c: Ditto.
* gcc.dg/compat/struct-by-value-17_x.c: Move some tests to new file to reduce code size.
* gcc.dg/compat/struct-by-value-17_y.c: Ditto.
* gcc.dg/compat/struct-by-value-17a_main.c: New file.
* gcc.dg/compat/struct-by-value-17a_x.c: Ditto.
* gcc.dg/compat/struct-by-value-17a_y.c: Ditto.
* gcc.dg/compat/struct-by-value-18_x.c: Move some tests to new file to reduce code size.
* gcc.dg/compat/struct-by-value-18_y.c: Ditto.
* gcc.dg/compat/struct-by-value-18a_main.c: New file.
* gcc.dg/compat/struct-by-value-18a_x.c: Ditto.
* gcc.dg/compat/struct-by-value-18a_y.c: Ditto.

From-SVN: r137396