Reduce flexelint config to the minimum necessary

lib/libvarnish/flint.lnt

-+libh mgt_event.h
-+libh ../../config.h
-
-+fan			// Allow anon unions
-
--dVARNISH_STATE_DIR="foo"
-
--emacro((???),va_arg)   // the va_arg() macro can yield 415, 416, 661, 662
-                        // 796 and 797 (out-of-bounds errors).
--elib(123)  // size is both a variable and a macro with args
--emacro(736, isnan)  // isnanf
-
-
--header(../../config.h)
-
--efile(451, "../../config.h")
-
-// Fix strchr() semtics, it can only return NULL if arg2 != 0
--sem(strchr, 1p, type(1), 2n == 0 ? (@p < 1p) : (@p < 1p || @p == 0 ))
-
--sem(lbv_assert, r_no)
--sem(lbv_xxxassert, r_no)
--sem(WS_Init, custodial(2))
--sem(http_Setup, custodial(2))
-
--ffc	// No automatic custody
-
--e763	// Redundant declaration for symbol '...' previously declared
-
--esym(534, sprintf)	// Ignoring return value of function
--esym(534, asprintf)	// Ignoring return value of function
--esym(534, printf)	// Ignoring return value of function
--esym(534, fprintf)	// Ignoring return value of function
--esym(534, memset)	// Ignoring return value of function
--esym(534, memcpy)	// Ignoring return value of function
--esym(534, memmove)	// Ignoring return value of function
--esym(534, strcpy)	// Ignoring return value of function
--esym(534, vsb_printf)	// Ignoring return value of function
--esym(534, vsb_cat)	// Ignoring return value of function
--esym(534, vsb_bcat)	// Ignoring return value of function
--esym(534, vsb_putc)	// Ignoring return value of function
--esym(534, strcat)	// Ignoring return value of function
--esym(534, strcpy)	// Ignoring return value of function
-
--emacro(506, isnan)	// constant value boolean
--emacro(747, isnan)	// significant coersion
--emacro(506, assert)	// constant value boolean
--emacro(774, HTTPH)	// always false
-
 -efunc(835, SHA256_Transform)	// A zero has been given as ___ argument to operator '___'
 -efunc(778, SHA256_Transform)	// Constant expression evaluates to 0 in operation '___'
++fan			// Allow anon unions
 
-// cache.h
--emacro(506, INCOMPL) // Constant value Boolean
-
-// cache_vcl.c
--e641	// Converting enum 'cli_status_e' to int
-
-// Review all below this line ///////////////////////////////////////////////
-
--e732   // Loss of sign (arg. no. 2) (int to unsigned
 -e713	// Loss of precision (assignment) (unsigned long long to long long)
--e712	// Loss of precision (assignment) (long long to
--e747	// Significant prototype coercion (arg. no. 2) long
-
-/*
-
--e767	// Macro redef (system queue.h vs ours )
 
--e506	// Constant value boolean
--e818	// Pointer parameter '...' could be declared as pointing to const
--e774	// Boolean within 'if' always evaluates to False
--e534	// Ignoring return value of function
--e557	// unrecog format
-
-*/
+-dVARNISH_STATE_DIR="foo"