ls1012a has separate input root clocks for core PLLs versus the platform
PLL, with the latter described as sysclk in the hw docs.
Update the qoriq-clock binding to allow a second input clock, named
"coreclk". If present, this clock will be used for the core PLLs.
Signed-off-by: Scott Wood <oss@buserror.net> Signed-off-by: Tang Yuantian <andy.tang@nxp.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>