ada: Fix LTO type mismatches in GNAT.Sockets.Thin

ada: Fix LTO type mismatches in GNAT.Sockets.Thin

The default implementation of GNAT.Sockets.Thin is mainly used on Linux and
the socklen_t type used in various routines of the BSD sockets C API is a
typedef for unsigned int there, so importing it as Interface.C.int will be
flagged as a type mismatch during LTO compilation.

gcc/ada/

	* libgnat/g-socthi.ads (C_Bind): Turn into inline function.
	(C_Getpeername): Likewise.
	(C_Getsockname): Likewise.
	(C_Getsockopt): Likewise.
	(C_Setsockopt): Likewise.
	(Nonreentrant_Gethostbyaddr): Likewise.
	* libgnat/g-socthi.adb (Syscall_Accept): Adjust profile.
	(Syscall_Connect): Likewise.
	(Syscall_Recvfrom): Likewise.
	(Syscall_Sendto): Likewise.
	(C_Bind): New function.
	(C_Accept): Adjust to above change for profiles.
	(C_Connect): Likewise.
	(C_Getpeername): New function.
	(C_Getsockname): Likewise.
	(C_Getsockopt): Likewise.
	(C_Recvfrom):  Adjust to above change for profiles.
	(C_Setsockopt): New function.
	(Nonreentrant_Gethostbyaddr): Likewise.