_WIN32 and_WIN64 are defined automatically by MinGW 4.8.3

Cleaned up an unnecessary define of _WIN32 and _WIN64

vfw32 is the name of the 64 bit version of vfw32, removed obsolete
if/else

Change-Id: Ib89767c4424abf85596bb56f8f1c7c9a2621cd83

Makefile.android

diff --git a/Makefile.android b/Makefile.android
index 92767f0..e509206 100644
--- a/Makefile.android
+++ b/Makefile.android
@@ -77,18 +77,9 @@
 ifeq ($(HOST_OS),windows)
   # we need Win32 features that are available since Windows 2000 Professional/Server (NT 5.0)
   MY_CFLAGS += -DWINVER=0x501
-  MY_CFLAGS += -D_WIN32
   # LARGEADDRESSAWARE gives more address space to 32-bit process
   MY_LDFLAGS32 += -Xlinker --large-address-aware
-  ifneq ($(HOST_IS_64_BIT),)
-    # Microsoft 64-bit compiler define both _WIN32 and _WIN64
-    MY_CFLAGS += -D_WIN64
-    # amd64-mingw32msvc- toolchain still name it vfw32.  May change it once amd64-mingw32msvc-
-    # is stabilized
-    MY_LDLIBS += -lvfw32
-  else
-    MY_LDLIBS += -lvfw32
-  endif
+  MY_LDLIBS += -lvfw32
 endif
 
 ifeq ($(HOST_ARCH),ppc)