nvidiafb: remove open_lock mutex

Remove mutex from the nvidiafb_open/nvidiafb_release functions as these
operations are mutexed at fb layer.

Signed-off-by: Alessio Igor Bogani <[e-mail]>
Cc: Krzysztof Helt <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/video/nvidia/nv_type.h

···
 #include <linux/types.h>
 #include <linux/i2c.h>
 #include <linux/i2c-algo-bit.h>
-#include <linux/mutex.h>
 #include <video/vga.h>
 
 #define NV_ARCH_04  0x04
···
 	RIVA_HW_STATE initial_state;
 	RIVA_HW_STATE *CurrentState;
 	struct vgastate vgastate;
-	struct mutex open_lock;
 	u32 pseudo_palette[16];
 	struct pci_dev *pci_dev;
 	u32 Architecture;

drivers/video/nvidia/nvidia.c

···
 {
 	struct nvidia_par *par = info->par;
 
-	mutex_lock(&par->open_lock);
-
 	if (!par->open_count) {
 		save_vga_x86(par);
 		nvidia_save_vga(par, &par->initial_state);
 	}
 
 	par->open_count++;
-	mutex_unlock(&par->open_lock);
 	return 0;
 }
 
···
 {
 	struct nvidia_par *par = info->par;
 	int err = 0;
-
-	mutex_lock(&par->open_lock);
 
 	if (!par->open_count) {
 		err = -EINVAL;
···
 
 	par->open_count--;
 done:
-	mutex_unlock(&par->open_lock);
 	return err;
 }
 
···
 
 	par = info->par;
 	par->pci_dev = pd;
-	mutex_init(&par->open_lock);
 	info->pixmap.addr = kzalloc(8 * 1024, GFP_KERNEL);
 
 	if (info->pixmap.addr == NULL)