vgabios: Create clext.h and use "clext_" as prefix for exported funcs.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
diff --git a/vgasrc/clext.c b/vgasrc/clext.c
index 7774ba3..7071749 100644
--- a/vgasrc/clext.c
+++ b/vgasrc/clext.c
@@ -5,7 +5,8 @@
 //
 // This file may be distributed under the terms of the GNU LGPLv3 license.
 
-#include "vgabios.h" // cirrus_init
+#include "clext.h" // clext_init
+#include "vgabios.h" // VBE_VENDOR_STRING
 #include "biosvar.h" // GET_GLOBAL
 #include "util.h" // dprintf
 #include "bregs.h" // struct bregs
@@ -392,7 +393,7 @@
 }
 
 int
-cirrus_set_video_mode(u8 mode, u8 noclearmem)
+clext_set_video_mode(u8 mode, u8 noclearmem)
 {
     dprintf(1, "cirrus mode %d\n", mode);
     SET_BDA(vbe_mode, 0);
@@ -932,7 +933,7 @@
  ****************************************************************/
 
 void
-cirrus_init(void)
+clext_init(void)
 {
     dprintf(1, "cirrus init\n");
     if (! cirrus_check())
diff --git a/vgasrc/clext.h b/vgasrc/clext.h
new file mode 100644
index 0000000..7d486a3
--- /dev/null
+++ b/vgasrc/clext.h
@@ -0,0 +1,9 @@
+#ifndef __CLEXT_H
+#define __CLEXT_H
+
+#include "types.h" // u8
+
+int clext_set_video_mode(u8 mode, u8 noclearmem);
+void clext_init(void);
+
+#endif // clext.h
diff --git a/vgasrc/vgabios.c b/vgasrc/vgabios.c
index d7c559a..203a394 100644
--- a/vgasrc/vgabios.c
+++ b/vgasrc/vgabios.c
@@ -20,6 +20,7 @@
 #include "stdvga.h" // stdvga_set_mode
 #include "geodelx.h" // geodelx_init
 #include "bochsvga.h" // bochsvga_init
+#include "clext.h" // clext_init
 
 // XXX
 #define DEBUG_VGA_POST 1
@@ -389,7 +390,7 @@
         regs->al = 0x30;
 
     if (CONFIG_VGA_CIRRUS) {
-        int ret = cirrus_set_video_mode(mode, noclearmem);
+        int ret = clext_set_video_mode(mode, noclearmem);
         if (ret)
             return;
     }
@@ -1213,7 +1214,7 @@
     SET_IVT(0x10, SEGOFF(get_global_seg(), (u32)entry_10));
 
     if (CONFIG_VGA_CIRRUS)
-        cirrus_init();
+        clext_init();
 
     // XXX - clear screen and display info
 
diff --git a/vgasrc/vgabios.h b/vgasrc/vgabios.h
index 0371f8c..c973d5f 100644
--- a/vgasrc/vgabios.h
+++ b/vgasrc/vgabios.h
@@ -65,10 +65,6 @@
 void vgafb_write_pixel(u8 color, u16 x, u16 y);
 u8 vgafb_read_pixel(u16 x, u16 y);
 
-// clext.c
-int cirrus_set_video_mode(u8 mode, u8 noclearmem);
-void cirrus_init(void);
-
 // vbe.c
 #define VBE_OEM_STRING "SeaBIOS VBE(C) 2011"
 #define VBE_VENDOR_STRING "SeaBIOS Developers"