parasite/x86: introduce&use builtin_memset

Don't use compiler-provided memset in parasite.

Fixes: commit 86434deba0b4 ("x86: dump TLS entries from GDT").

Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

criu/include/asm-generic/string.h

@@ -46,4 +46,15 @@ static always_inline int builtin_strncmp(const char *cs, const char *ct, size_t
 }
 #endif
 
+#ifndef HAS_BUILTIN_MEMSET
+static always_inline void builtin_memset(void *s, const int c, size_t count)
+{
+	char *dest = s;
+	size_t i = 0;
+
+	while (i < count)
+		dest[i++] = (char) c;
+}
+#endif
+
 #endif /* __CR_ASM_GENERIC_STRING_H__ */

criu/pie/parasite.c

@@ -20,8 +20,6 @@
 #include "tty.h"
 #include "aio.h"
 
-#include <string.h>
-
 #include "asm/parasite.h"
 #include "restorer.h"