Sync with vanilla OpenSSH code (/usr/src/usr.bin/ssh/poly1305.c)
Perl's U8TO32_LE macro fails to parenthesize its argument on sparc64 in
hv_func.h, leading to a build failure.  This patch could be removed once we
ship Perl>=5.28.
Index: src/chacha/poly1305.c
--- src/chacha/poly1305.c.orig
+++ src/chacha/poly1305.c
@@ -11,13 +11,11 @@
 
 #define mul32x32_64(a,b) ((uint64_t)(a) * (b))
 
-#ifndef U8TO32_LE
 #define U8TO32_LE(p) \
 	(((uint32_t)((p)[0])) | \
 	 ((uint32_t)((p)[1]) <<  8) | \
 	 ((uint32_t)((p)[2]) << 16) | \
 	 ((uint32_t)((p)[3]) << 24))
-#endif
 
 #define U32TO8_LE(p, v) \
 	do { \