Add OPENSSL_INCLUDE to the CFLAGS for ssl.c and tcptls.c.

Without this flag, those files will compile with the system installed
OpenSSL headers (if they exist). This is a real bummer if a different
path was specified using --with-ssl=

(closes issue ASTERISK-20392)
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Merged revisions 372682 from http://svn.asterisk.org/svn/asterisk/branches/1.8
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Recorded merge of revisions 372695 from http://svn.asterisk.org/svn/asterisk/branches/10
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Recorded merge of revisions 372696 from http://svn.asterisk.org/svn/asterisk/branches/11


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@372699 65c4cc65-6c06-0410-ace0-fbb531ad65f3

main/Makefile

@@ -194,6 +194,8 @@ ASTSSL_SO_VERSION=1
 
 ASTSSL_LDLIBS=-L. -lasteriskssl
 
+libasteriskssl.o: _ASTCFLAGS+=$(OPENSSL_INCLUDE)
+
 ifeq ($(findstring darwin,$(OSARCH)),) # not Darwin
 ASTSSL_LIB:=libasteriskssl.so
 
@@ -235,6 +237,8 @@ endif
 
 endif
 
+tcptls.o: _ASTCFLAGS+=$(OPENSSL_INCLUDE)
+
 $(MAIN_TGT): $(OBJS) $(ASTSSL_LIB) $(LIBEDIT_OBJ) $(AST_EMBED_LDSCRIPTS)
 	@$(CC) -c -o buildinfo.o $(_ASTCFLAGS) buildinfo.c $(ASTCFLAGS)
 	$(ECHO_PREFIX) echo "   [LD] $(OBJS) $(LIBEDIT_OBJ) $(AST_EMBED_LDSCRIPTS) -> $@"