syspart.c: klibc specific fix for pivot_root syscall

Compiling against klibc we invoke directly the syscall
(generated into syscall stubs in their own files).
See /usr/klibc/SYSCALLS.def

Fixing:
| syspart.c: In function 'switch_root':
| syspart.c:26:2: warning: implicit declaration of function 'syscall' [-Wimplicit-function-declaration]
|   if (syscall(SYS_pivot_root, ".", "boot")) {
|   ^
| syspart.c:26:14: error: 'SYS_pivot_root' undeclared (first use in this function)
|   if (syscall(SYS_pivot_root, ".", "boot")) {
|               ^

Signed-off-by: Andrea Adami <[email protected]>

Author: andrea-adami

syspart.c

@@ -3,7 +3,12 @@
 
 #include <errno.h>
 #include <stdlib.h>
+
+#ifndef __KLIBC__
 #include <sys/syscall.h>
+#else
+#include <sys/mount.h>
+#endif /* __KLIBC__ */
 #include <unistd.h>
 
 #include "debug.h"
@@ -23,7 +28,11 @@ int open_dir_to_clean(void)
 int switch_root(void)
 {
 	DEBUG("Pivoting root\n");
+#ifndef __KLIBC__
 	if (syscall(SYS_pivot_root, ".", "boot")) {
+#else
+	if (pivot_root(".", "boot") < 0) {
+#endif /* __KLIBC__ */
 		ERROR("Unable to pivot root: %d\n", errno);
 		return -1;
 	}