Remove gmake-exclusive ifeq statements in Makefile

Makefile

@@ -1,19 +1,3 @@
-# The GPLv2 License (GPLv2)
-# Copyright (c) 2023 Jeremy Baxter
-# 
-# esv is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation; either version 2 of the License, or
-# (at your option) any later version.
-# 
-# esv is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-# 
-# You should have received a copy of the GNU General Public License
-# along with esv.  If not, see <http://www.gnu.org/licenses/>.
-
 PROG      = esv
 IMPORT    = import
 PREFIX    = /usr/local
@@ -23,16 +7,6 @@ DC     = ldc2
 CFLAGS = -O -I${IMPORT}
 OBJS   = main.o esv.o ini.o
 
-ifeq (${DEBUG},)
-	CFLAGS += -release
-endif
-
-ifneq (${WI},)
-	CFLAGS += -wi
-else
-	CFLAGS += -w
-endif
-
 all: esv
 
 esv: ${OBJS}