Support utimensat_time64 on 32bit architectures (#303)

This is the Y2038 function for utimensat and AFAICT the only one we care about.
There are a few other ones that are referred to by the kompac extension
but a kernel with the Y2038 syscalls are not going to be old enough to need those...

src/syscall/enter.c

@@ -396,6 +396,7 @@ int translate_syscall_enter(Tracee *tracee)
 	case PR_newfstatat:
 	case PR_statx:
 	case PR_utimensat:
+	case PR_utimensat_time64:
 	case PR_name_to_handle_at:
 		dirfd = peek_reg(tracee, CURRENT, SYSARG_1);
 

src/syscall/seccomp.c

@@ -409,6 +409,7 @@ static FilteredSysnum proot_sysnums[] = {
 	{ PR_uselib,		0 },
 	{ PR_utime,		0 },
 	{ PR_utimensat,		0 },
+	{ PR_utimensat_time64,		0 },
 	{ PR_utimes,		0 },
 	{ PR_wait4,		FILTER_SYSEXIT },
 	{ PR_waitpid,		FILTER_SYSEXIT },

src/syscall/sysnums-arm.h

@@ -340,4 +340,5 @@ static const Sysnum sysnums_arm[] = {
 	[ 381 ] = PR_sched_getattr,
 	[ 382 ] = PR_renameat2,
 	[ 397 ] = PR_statx,
+	[ 412 ] = PR_utimensat_time64,
 };

src/syscall/sysnums-i386.h

@@ -352,4 +352,5 @@ static const Sysnum sysnums_i386[] = {
 	[ 352 ] = PR_sched_getattr,
 	[ 353 ] = PR_renameat2,
 	[ 383 ] = PR_statx,
+	[ 412 ] = PR_utimensat_time64,
 };

src/syscall/sysnums.list

@@ -429,3 +429,4 @@ SYSNUM(x32_vmsplice)
 SYSNUM(x32_waitid)
 SYSNUM(x32_writev)
 SYSNUM(statx)
+SYSNUM(utimensat_time64)