vsftpd 3.0.2

Update to latest stable release, simplify OpenSSL option, and add a new patch for incompatible linker flags.
I meant that the LDFLAGS my patch removes aren't critical, as they aren't in the version currently in Homebrew. Leaving those flags in will break compilation.

*Flags in the 2.3.4 Makefile*
```Makefile
# Makefile for systems with GNU tools
CC 	=	gcc
INSTALL	=	install
IFLAGS  = -idirafter dummyinc
#CFLAGS = -g
CFLAGS	=	-O2 -Wall -W -Wshadow #-pedantic -Werror -Wconversion

LIBS	=	`./vsf_findlibs.sh`
LINK	=	-Wl,-s
```

The patch is necessary to allow compilation with clang.