Add recvmmsg & sendmmsg syscall number for loongarch64 (#13097)

Motivation:
Call correct recvmmsg and sendmmsg on loongarch64.

Modification:
Add #elif declarations to ensure we pick the correct syscall number for loongarch64.

Result:
Pick the correct syscall number depending on the system architecture.

transport-native-epoll/src/main/c/netty_epoll_native.c

@@ -102,6 +102,9 @@ struct mmsghdr {
 #elif defined(__i386__)
 // See https://github.com/torvalds/linux/blob/v5.4/arch/x86/entry/syscalls/syscall_32.tbl
 #define SYS_recvmmsg 337
+#elif defined(__loongarch64)
+// See https://github.com/torvalds/linux/blob/v6.1/include/uapi/asm-generic/unistd.h
+#define SYS_recvmmsg 243
 #else
 #define SYS_recvmmsg -1
 #endif
@@ -115,6 +118,9 @@ struct mmsghdr {
 #elif defined(__i386__)
 // See https://github.com/torvalds/linux/blob/v5.4/arch/x86/entry/syscalls/syscall_32.tbl
 #define SYS_sendmmsg 345
+#elif defined(__loongarch64)
+// See https://github.com/torvalds/linux/blob/v6.1/include/uapi/asm-generic/unistd.h
+#define SYS_sendmmsg 269
 #else
 #define SYS_sendmmsg -1
 #endif