vm/qubes-rpc: move set_(non)?block to ioall.c as can be used not only in qrexec

qubes_rpc/ioall.c

@@ -32,6 +32,17 @@ void perror_wrapper(char * msg)
 	errno=prev;
 }
 
+void set_nonblock(int fd)
+{
+	int fl = fcntl(fd, F_GETFL, 0);
+	fcntl(fd, F_SETFL, fl | O_NONBLOCK);
+}
+
+void set_block(int fd)
+{
+	int fl = fcntl(fd, F_GETFL, 0);
+	fcntl(fd, F_SETFL, fl & ~O_NONBLOCK);
+}
 
 int write_all(int fd, void *buf, int size)
 {

qubes_rpc/ioall.h

@@ -1,3 +1,5 @@
 int write_all(int fd, void *buf, int size);
 int read_all(int fd, void *buf, int size);
 int copy_fd_all(int fdout, int fdin);
+void set_nonblock(int fd);
+void set_block(int fd);