lib/sha*.c: Update header list

Cleanup the list of headers we include here. For the tools build we only
need to exclude <cyclic.h> as that's used by the target build for the
prototype for schedule(), and we don't need to get that via
<watchdog.h>. We can also make use of our <string.h> intentionally
existing as a redirection to <linux/string.h> to reduce ifdef'd lines.

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Rini <trini@konsulko.com>

lib/sha1.c

@@ -17,12 +17,9 @@
 #endif
 
 #ifndef USE_HOSTCC
-#include <common.h>
-#include <linux/string.h>
-#else
-#include <string.h>
+#include <cyclic.h>
 #endif /* USE_HOSTCC */
-#include <watchdog.h>
+#include <string.h>
 #include <u-boot/sha1.h>
 
 #include <linux/compiler_attributes.h>

lib/sha256.c

@@ -6,12 +6,9 @@
  */
 
 #ifndef USE_HOSTCC
-#include <common.h>
-#include <linux/string.h>
-#else
-#include <string.h>
+#include <cyclic.h>
 #endif /* USE_HOSTCC */
-#include <watchdog.h>
+#include <string.h>
 #include <u-boot/sha256.h>
 
 #include <linux/compiler_attributes.h>

lib/sha512.c

@@ -11,13 +11,9 @@
  */
 
 #ifndef USE_HOSTCC
-#include <common.h>
-#include <linux/string.h>
-#else
-#include <string.h>
+#include <cyclic.h>
 #endif /* USE_HOSTCC */
 #include <compiler.h>
-#include <watchdog.h>
 #include <u-boot/sha512.h>
 
 const uint8_t sha384_der_prefix[SHA384_DER_LEN] = {