[Toybox] Android support

[enh]

i notice you just added sethostname to portability.c which causes this
warning on Android:

external/toybox/lib/portability.c:70:3: warning: implicit declaration
of function 'syscall' [-Wimplicit-function-declaration]
   return syscall(__NR_sethostname, name, len);

the correct #include would have been #include <sys/syscall.h>, not
<asm/unistd.h>. you really shouldn't ever #include an asm/ file.

i'm also curious about what your target is. AOSP master has
sethostname, so you don't need any of this. (but you do need some
other changes.)

anyway, let me know what you're trying to do and i'll try to help.

 --elliott (bionic maintainer)

 1416508381.0