Make gensyscalls.py use the ALIAS_SYMBOL macro.

Change-Id: Ib94c0abb6fc85126ecc5ed3f1962b2b8b90b9952
diff --git a/libc/arch-arm64/syscalls/pread64.S b/libc/arch-arm64/syscalls/pread64.S
index eafc044..6c9f0e9 100644
--- a/libc/arch-arm64/syscalls/pread64.S
+++ b/libc/arch-arm64/syscalls/pread64.S
@@ -13,5 +13,4 @@
     ret
 END(pread64)
 
-    .globl pread
-    .equ pread, pread64
+ALIAS_SYMBOL(pread, pread64)