[PATCH] libgo: Explicitly define SYS_timer_settime for 32-bit musl targets

[soeren@soeren-tempel.net]

From: Sören Tempel <soeren+git@soeren-tempel.net>

On 32-bit systems, musl only defines SYS_timer_settime32 not
SYS_timer_settime. This causes the following compilation error:

            os_linux.go:251:30: error: reference to undefined name '_SYS_timer_settime'
              251 |         return int32(syscall(_SYS_timer_settime, uintptr(timerid), uintptr(flags), uintptr(unsafe.Pointer(new)), uintptr(unsafe.Pointer(old)), 0, 0))
                  |                              ^

This commit fixes this error by "aliasing" SYS_timer_settime to
SYS_timer_settime32 if the latter is defined. This is also what
musl does internally [1].

[1]: https://git.musl-libc.org/cgit/musl/tree/src/internal/syscall.h?h=v1.2.3#n212
---
 libgo/sysinfo.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/libgo/sysinfo.c b/libgo/sysinfo.c
index fc021099..6848fba5 100644
--- a/libgo/sysinfo.c
+++ b/libgo/sysinfo.c
@@ -354,6 +354,12 @@ enum {
 };
 #endif
 
+// musl libc does not have SYS_timer_settime on 32-bit platforms
+// but defines SYS_timer_settime32 instead, alias accordingly.
+#ifdef SYS_timer_settime32
+#define SYS_timer_settime SYS_timer_settime32
+#endif
+
 #if defined(HAVE_LOFF_T)
 // loff_t can be defined as a macro; for -fgo-dump-spec make sure we
 // see a typedef.