logging.c: Properly indent and ignore one syntax-check rule

With our fix of mkostemp (pushed as 2b435c15) we define a macro
to compile with uclibc. However, this definition is conditional
and thus needs to be properly indented. Moreover, with this definition
sc_prohibit_mkstemp syntax-check rule keeps yelling:

  src/util/logging.c:63:# define mkostemp(x,y) mkstemp(x)
  maint.mk: use mkostemp with O_CLOEXEC instead of mkstemp

Therefore we should ignore this file for this rule.

cfg.mk

@@ -817,3 +817,5 @@ exclude_file_name_regexp--sc_unmarked_diagnostics = \
   ^(docs/apibuild.py|tests/virt-aa-helper-test)$$
 
 exclude_file_name_regexp--sc_size_of_brackets = cfg.mk
+
+exclude_file_name_regexp--sc_prohibit_mkstemp = ^src/util/logging\.c$$

src/util/logging.c

@@ -60,7 +60,7 @@
 
 #ifdef __UCLIBC__
 /* uclibc does not implement mkostemp GNU extention */
-#define mkostemp(x,y) mkstemp(x)
+# define mkostemp(x,y) mkstemp(x)
 #endif
 
 VIR_ENUM_DECL(virLogSource)