Dereference symlinks when copying files.

The prebuilts are made available to the build via symlinks so be sure
dereference them.

Bug: 74835164
Test: `build_mixed gsi device dist` where device contained symlinks
Merged-In: I4d8139ec17405037f2764691d026c2f9ad42a3fb
Change-Id: I4d8139ec17405037f2764691d026c2f9ad42a3fb
(cherry picked from commit bdb3f4f7de52554fbf888bb11f0519d5600abe1e)
1 file changed