asm-generic: add sys_accept4 to unistd.h
asm-generic: add sys_accept4 to unistd.h

Code review has shown that the generic version of
unistd.h is missing a reference to the accept4
system call. This was not noticed before because
most architectures handle this through sys_socketcall.

Signed-off-by: Arnd Bergmann <f2c659f01951776204a6c5b902787d9019fbeebd@arndb.de>

TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs