[media] atomisp: don't treat warnings as errors

Several atomisp files use:
	 ccflags-y += -Werror

As, on media, our usual procedure is to use W=1, and atomisp
has *a lot* of warnings with such flag enabled,like:

./drivers/staging/media/atomisp/pci/atomisp2/css2400/hive_isp_css_common/host/system_local.h:62:26: warning: 'DDR_BASE' defined but not used [-Wunused-const-variable=]

At the end, it causes our build to fail, impacting our workflow.

So, remove this crap. If one wants to force -Werror, he
can still build with it enabled by passing a parameter to
make.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/staging/media/atomisp/i2c/Makefile

@@ -19,5 +19,3 @@ obj-$(CONFIG_VIDEO_AP1302)     += ap1302.o
 
 obj-$(CONFIG_VIDEO_LM3554) += lm3554.o
 
-ccflags-y += -Werror
-

drivers/staging/media/atomisp/i2c/imx/Makefile

@@ -4,5 +4,3 @@ imx1x5-objs := imx.o drv201.o ad5816g.o dw9714.o dw9719.o dw9718.o vcm.o otp.o o
 
 ov8858_driver-objs := ../ov8858.o dw9718.o vcm.o
 obj-$(CONFIG_VIDEO_OV8858)     += ov8858_driver.o
-
-ccflags-y += -Werror

drivers/staging/media/atomisp/i2c/ov5693/Makefile

 obj-$(CONFIG_VIDEO_OV5693) += ov5693.o
-
-ccflags-y += -Werror

drivers/staging/media/atomisp/pci/atomisp2/Makefile

@@ -351,5 +351,5 @@ DEFINES := -DHRT_HW -DHRT_ISP_CSS_CUSTOM_HOST -DHRT_USE_VIR_ADDRS -D__HOST__
 DEFINES += -DATOMISP_POSTFIX=\"css2400b0_v21\" -DISP2400B0
 DEFINES += -DSYSTEM_hive_isp_css_2400_system -DISP2400
 
-ccflags-y += $(INCLUDES) $(DEFINES) -fno-common -Werror
+ccflags-y += $(INCLUDES) $(DEFINES) -fno-common