[OpenMP] Ignore .eggs file in OpenMP

The OMPD patches introduces GDB plugin. When it is built, it will create a
coulple of temp files in `.eggs`. This patch add it into `.gitignore` in case it
messed up the git tracking.

Reviewed By: jhuber6

Differential Revision: https://reviews.llvm.org/D129711

openmp/.gitignore

@@ -20,6 +20,8 @@
 .sw?
 #OS X specific files.
 .DS_store
+# Python egg files
+*.eggs
 
 #==============================================================================#
 # Explicit files to ignore (only matches one).