these macros have the same distinct definition on blackfin, frv, m68k,
mips, sparc and xtensa kernels. POLLMSG and POLLRDHUP additionally
differ on sparc.
the definitions are generic for all kernel archs. exposure of these
macros now only occurs on the same feature test as for the function
accepting them, which is believed to be more correct.
this typo did not result in an erroneous setjmp with at least binutils
2.22 but fix it for clarity and compatibility with potentially stricter
sh assemblers.
