we change some variables in the Makefile
for a better handling in gentoo ebuild

Signed-off-by: Joerg Bornkessel <hd_brummy@gentoo.org> 2021/Feb/11
diff -Naur vdr-2.4.6.orig/Makefile vdr-2.4.6/Makefile
--- vdr-2.4.6.orig/Makefile	2020-06-27 11:13:04.000000000 +0200
+++ vdr-2.4.6/Makefile	2020-08-08 18:16:02.519719542 +0200
@@ -65,7 +65,7 @@
 
 # Output control
 
-ifdef VERBOSE
+ifeq ($(VERBOSE),1)
 Q =
 else
 Q = @
@@ -100,7 +100,7 @@
 ifdef HDRDIR
 HDRDIR   := -I$(HDRDIR)
 endif
-ifndef NO_KBD
+ifeq ($(USE_KBD),1)
 DEFINES += -DREMOTE_KBD
 endif
 ifdef REMOTE
@@ -109,12 +109,12 @@
 ifdef VDR_USER
 DEFINES += -DVDR_USER=\"$(VDR_USER)\"
 endif
-ifdef BIDI
+ifeq ($(BIDI),1)
 INCLUDES += $(shell $(PKG_CONFIG) --cflags fribidi)
 DEFINES += -DBIDI
 LIBS += $(shell $(PKG_CONFIG) --libs fribidi)
 endif
-ifdef SDNOTIFY
+ifeq ($(SDNOTIFY),1)
 INCLUDES += $(shell $(PKG_CONFIG) --silence-errors --cflags libsystemd-daemon || $(PKG_CONFIG) --cflags libsystemd)
 DEFINES += -DSDNOTIFY
 LIBS += $(shell $(PKG_CONFIG) --silence-errors --libs libsystemd-daemon || $(PKG_CONFIG) --libs libsystemd)