openocd: fix simple cases of NULL comparison

openocd: fix simple cases of NULL comparison

There are more than 1000 NULL comparisons to be aligned to the
coding style.
For recurrent NULL comparison it's preferable using trivial
scripts in order to minimize the review effort.

Patch generated automatically with the command:
	sed -i PATTERN $(find src/ -type f)
where PATTERN is in the list:
	's/(\([a-z][a-z0-9_]*\) == NULL)/(!\1)/g'
	's/(\([a-z][a-z0-9_]*->[a-z][a-z0-9_]*\) == NULL)/(!\1)/g'
	's/(\([a-z][a-z0-9_]*\.[a-z][a-z0-9_]*\) == NULL)/(!\1)/g'

	's/(\([a-z][a-z0-9_]*\) != NULL)/(\1)/g'
	's/(\([a-z][a-z0-9_]*->[a-z][a-z0-9_]*\) != NULL)/(\1)/g'
	's/(\([a-z][a-z0-9_]*\.[a-z][a-z0-9_]*\) != NULL)/(\1)/g'

	's/(NULL == \([a-z][a-z0-9_]*\))/(!\1)/g'
	's/(NULL == \([a-z][a-z0-9_]*->[a-z][a-z0-9_]*\))/(!\1)/g'
	's/(NULL == \([a-z][a-z0-9_]*\.[a-z][a-z0-9_]*\))/(!\1)/g'

	's/(NULL != \([a-z][a-z0-9_]*\))/(\1)/g'
	's/(NULL != \([a-z][a-z0-9_]*->[a-z][a-z0-9_]*\))/(\1)/g'
	's/(NULL != \([a-z][a-z0-9_]*\.[a-z][a-z0-9_]*\))/(\1)/g'

Change-Id: Ida103e325d6d0600fb69c0b7a1557ee969db4417
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: http://openocd.zylin.com/6350
Tested-by: jenkins