Yes, using attributes. Put something like this in your .gitattributes file (create it if it doesn't exist):

*.sln binary
*.suo binary
*.vcxproj binary

Here binary is actually a predefined macro, equivalent to -diff -merge -text.

If you want to still be able to see the diff, you can use:

*.sln -merge -text

This way, the *.sln files won't be merged, not have eol normalized, but meanwhile diff-able.