meson.build: Use library() to build libflashrom

Use library() instead of both_libraries() to build libflashrom. The
built-in option `default-library` can be used to decide which kind of
libraries should be built. Make `both` the default and throw an error in
the case someone tries to build the classic_cli with a shared library.

Change-Id: I27f10fdf1227795a9a3b4e050a2d708b58f10ee7
Signed-off-by: Thomas Heijligen <thomas.heijligen@secunet.com>
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M meson.build
1 file changed, 27 insertions(+), 3 deletions(-)