tools/e2fsprogs: fix build under macos

macos doesn't define a loff_t type, the native off_t type being 64bit
anyway.

Persuade e2fsprogs to accept off_t instead on macos

Signed-off-by: Kevin Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>

tools/e2fsprogs/Makefile

@@ -21,7 +21,7 @@ HOST_BUILD_PARALLEL:=1
 include $(INCLUDE_DIR)/host-build.mk
 
 ifneq ($(shell $(HOSTCC) --version | grep clang),)
-  HOST_CFLAGS += -D__GNUC_PREREQ\(...\)=0
+  HOST_CFLAGS += -D__GNUC_PREREQ\(...\)=0 -Dloff_t=off_t
 endif
 HOST_CFLAGS += $(FPIC)