Per review: A72 was dropped from the default DYNAMIC_CORE list in
#4389 to limit arm64 binary size. Restore the A57 alias for default
DYNAMIC_ARCH; TARGET=CORTEXA72 and DYNAMIC_LIST=CORTEXA72 still get
the dedicated 6x8 kernels.
Co-authored-by: Cursor <cursoragent@cursor.com>