Be more systematic about parens in C source code

Be more systematic about putting space before paren in calls,
and in avoiding unnecessary parentheses in macros.
This was partly inspired by my wading through gcc -E output
while debugging something else, and seeing too many parens.

This patch does not change the generated .o files on my platform.

admin/notes/java

@@ -445,7 +445,7 @@ loaded by the special invocation:
 where ``static'' defines a section of code which will be run upon the
 object (containing class) being loaded.  This is like:
 
-  __attribute__((constructor))
+  __attribute__ ((constructor))
 
 on systems where shared object constructors are supported.