clk: remove sirf prima2/atlas drivers

The CSR SiRF prima2/atlas platforms are getting removed, so this driver
is no longer needed.

Cc: Barry Song <baohua@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20210120131026.1721788-4-arnd@kernel.org
Acked-by: Barry Song <baohua@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

Author: arndb

Documentation/devicetree/bindings/clock/csr,atlas7-car.txt

@@ -103,7 +103,6 @@ obj-y					+= renesas/
 obj-$(CONFIG_ARCH_ROCKCHIP)		+= rockchip/
 obj-$(CONFIG_COMMON_CLK_SAMSUNG)	+= samsung/
 obj-$(CONFIG_CLK_SIFIVE)		+= sifive/
-obj-$(CONFIG_ARCH_SIRF)			+= sirf/
 obj-$(CONFIG_ARCH_SOCFPGA)		+= socfpga/
 obj-$(CONFIG_ARCH_AGILEX)		+= socfpga/
 obj-$(CONFIG_ARCH_STRATIX10)		+= socfpga/