use pkg-config to configure with fdk-aac

configure.ac

@@ -237,7 +237,7 @@ fi
 # checking for fdk aac
 if test "x$enable_fdkaac" = "xyes"
 then
-  AC_CHECK_HEADER([fdk-aac/aacenc_lib.h], [],
+  PKG_CHECK_MODULES([FDKAAC], [fdk-aac >= 0.1.0], [],
     [AC_MSG_ERROR([please install libfdk-aac-dev or fdk-aac-devel])])
 fi
 

sesman/chansrv/Makefile.am

@@ -24,8 +24,8 @@ CHANSRV_EXTRA_LIBS += $(FUSE_LIBS)
 endif
 
 if XRDP_FDK_AAC
-AM_CPPFLAGS += -DXRDP_FDK_AAC
-CHANSRV_EXTRA_LIBS += -lfdk-aac
+AM_CPPFLAGS += -DXRDP_FDK_AAC $(FDKAAC_CFLAGS)
+CHANSRV_EXTRA_LIBS += $(FDKAAC_LIBS)
 endif
 
 if XRDP_OPUS