Header fixes:

* Do not include system headers in shared files (stdlib.h).
* Don't include lcd.h only once in each driver.
* Remove some unnecessary headers from driver (e.g. syslog.h)
* Include <poll.h> instead of <sys/poll.h>
* Spelling fixes.

clients/lcdvc/lcd_link.c

@@ -19,6 +19,7 @@
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <errno.h>
+#include <stdlib.h>
 
 #include "lcd_link.h"
 #include "vc_link.h"

clients/lcdvc/lcdvc.c

@@ -20,6 +20,7 @@
 #include <signal.h>
 #include <fcntl.h>
 #include <errno.h>
+#include <stdlib.h>
 
 #include "getopt.h"
 

clients/lcdvc/vc_link.c

@@ -19,6 +19,7 @@
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <errno.h>
+#include <stdlib.h>
 
 #include "lcdvc.h"
 #include "vc_link.h"
@@ -79,7 +80,7 @@ int read_vcdata(void)
 			if (vc_buf == NULL) {
 				report(RPT_ERR, "malloc failure: %s", strerror(errno));
 				return -1;
-			}	
+			}
 			memset(vc_buf, ' ', vc_width * vc_height);
 		}
 	}