Remove obsoleted platform/external/genext2fs

Bug: 19282953
Change-Id: I30b6ebbb2f8002f3aaa6cbdca7e05c840da7d380

default.xml

@@ -135,7 +135,6 @@
   <project path="external/fonttools" name="platform/external/fonttools" />
   <project path="external/freetype" name="platform/external/freetype" groups="pdk" />
   <project path="external/fsck_msdos" name="platform/external/fsck_msdos" groups="pdk-cw-fs" />
-  <project path="external/genext2fs" name="platform/external/genext2fs" groups="pdk-cw-fs" />
   <project path="external/giflib" name="platform/external/giflib" groups="pdk-cw-fs,qcom_msm8x26" />
   <project path="external/glide" name="platform/external/glide" />
   <project path="external/google-fonts/coming-soon" name="platform/external/google-fonts/coming-soon" groups="pdk-cw-fs" />