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

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.