awk: tighten rules in action parsing

Disallow:
    BEGIN
	{ action }  - must start on the same line
Disallow:
    func f()
	print "hello" - must be in {...}

function                                             old     new   delta
chain_until_rbrace                                     -      41     +41
parse_program                                        307     336     +29
chain_group                                          649     616     -33
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 1/1 up/down: 70/-33)             Total: 37 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
1 file changed