don't hardcode -O3

Index: build/premake/premake5/build/gmake2.bsd/Premake5.make
--- build/premake/premake5/build/gmake2.bsd/Premake5.make.orig
+++ build/premake/premake5/build/gmake2.bsd/Premake5.make
@@ -36,8 +36,8 @@ TARGETDIR = ../../bin/release
 TARGET = $(TARGETDIR)/premake5
 OBJDIR = obj/Release/Premake5
 DEFINES += -DPREMAKE_COMPRESSION -DCURL_STATICLIB -DPREMAKE_CURL -DNDEBUG -DLUA_USE_POSIX -DLUA_USE_DLOPEN
-ALL_CFLAGS += $(CFLAGS) $(ALL_CPPFLAGS) -O3 -Wall -Wextra
-ALL_CXXFLAGS += $(CXXFLAGS) $(ALL_CPPFLAGS) -O3 -Wall -Wextra -fno-stack-protector
+ALL_CFLAGS += $(CFLAGS) $(ALL_CPPFLAGS) -Wall -Wextra
+ALL_CXXFLAGS += $(CXXFLAGS) $(ALL_CPPFLAGS) -Wall -Wextra -fno-stack-protector
 LIBS += bin/Release/liblua-lib.a bin/Release/libzip-lib.a bin/Release/libzlib-lib.a bin/Release/libcurl-lib.a bin/Release/libmbedtls-lib.a -lm
 LDDEPS += bin/Release/liblua-lib.a bin/Release/libzip-lib.a bin/Release/libzlib-lib.a bin/Release/libcurl-lib.a bin/Release/libmbedtls-lib.a
 ALL_LDFLAGS += $(LDFLAGS) -s -rdynamic
