checkpatch: Silence undesired warnings

Silence "WARNING: Prefer 'unsigned int' to bare use of 'unsigned'".
OCF uses that convention for a long time and it would require change
in many places to enforce the one suggested by checkpatch.pl.

Silence "WARNING: do not add new typedefs". Typedefs are extensively used
in OCF.

Silence attribute macros warning. It breaks compilation in pyOCF.

Signed-off-by: Robert Baldyga <[email protected]>

Author: Robert Baldyga

.checkpatch.conf

@@ -7,6 +7,9 @@
 --ignore PREFER_PR_LEVEL
 --ignore SPDX_LICENSE_TAG
 --ignore SPLIT_STRING
+--ignore UNSPECIFIED_INT
+--ignore NEW_TYPEDEFS
+--ignore PREFER_DEFINED_ATTRIBUTE_MACRO
 
 --exclude .github
 --exclude doc