Remove "sha1.h".

This was removed from bionic by commit c82c0b7e072491da4818e7de37411fbb2055fce1
in 2014-06. The symbols are still in NDK cruft for LP32, but no longer in the
NDK's libc.so. Microsoft points out that we should probably remove the header
too.

Bug: 11156955
Change-Id: Id463f8f20d3d8c4428f6aecb317577d78ccad215

ndk/platforms/android-3/include/sha1.h

@@ -1,31 +0,0 @@
-/*	$NetBSD: sha1.h,v 1.13 2005/12/26 18:41:36 perry Exp $	*/
-
-/*
- * SHA-1 in C
- * By Steve Reid <steve@edmweb.com>
- * 100% Public Domain
- */
-
-#ifndef _SYS_SHA1_H_
-#define	_SYS_SHA1_H_
-
-#include <sys/cdefs.h>
-#include <sys/types.h>
-
-#define SHA1_DIGEST_LENGTH		20
-#define SHA1_DIGEST_STRING_LENGTH	41
-
-typedef struct {
-	uint32_t state[5];
-	uint32_t count[2];
-	u_char buffer[64];
-} SHA1_CTX;
-
-__BEGIN_DECLS
-void	SHA1Transform(uint32_t[5], const u_char[64]);
-void	SHA1Init(SHA1_CTX *);
-void	SHA1Update(SHA1_CTX *, const u_char *, u_int);
-void	SHA1Final(u_char[SHA1_DIGEST_LENGTH], SHA1_CTX *);
-__END_DECLS
-
-#endif /* _SYS_SHA1_H_ */