fix bug added by MUSL support for ARM32

[clemdiep]

Beside various bug fixes, I had to:

• Remove logic in serial_gwinsize to get terminal size, because it was originally inteded to work with some custom patch on QEMU which aren't implemented.
• Add two ARM32 specifics syscalls to manage TLS. They can't be set in the common syscall table used by syscall_handle as they don't follow the same convention (number is way to big for a table).
• Rework a bit syscall.tbl to indicate the SO3 function name to use (without the prefix added by SYSCALL_DEFINE). This is because in syscall.h.in (copied from MUSL), the syscall clock_gettime is named clock_gettime64 with the same interface and so remove the need to add a function which will just call clock_gettime as well as removing manual edit of syscall.h.in to avoid futur bug if that file is updated from MUSL

[daniel-rossier]

Nice work!