gcc-plugins: Fix build for upcoming GCC release

The upcoming GCC release has refactored the gimple plugin interface a
bit and unless gimple-iterator.h is included before gimple-fold.h I end
up with a bunch of missing declarations when building the stack
protector plugin.

Link: https://inbox.sourceware.org/gcc-patches/CAFiYyc2q%2Bc-0uZb-zAskmR_U%2BM%2BxQfp-W00ZbLErfjx=j5qHGg@mail.gmail.com/
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
1 file changed