clk: sifive: fu540-prci: Declare static const variable 'prci_clk_fu540' where it's used

Fixes the following W=1 kernel build warning(s):

drivers/clk/sifive/fu540-prci.h:16:35: warning: ‘prci_clk_fu540’ defined but not used [-Wunused-const-variable=]
drivers/clk/sifive/fu540-prci.h:16:35: warning: ‘prci_clk_fu540’ defined but not used [-Wunused-const-variable=]

Cc: Michael Turquette <[e-mail]>
Cc: Stephen Boyd <[e-mail]>
Cc: Paul Walmsley <[e-mail]>
Cc: Palmer Dabbelt <[e-mail]>
Cc: Pragnesh Patel <[e-mail]>
Cc: Zong Li <[e-mail]>
Cc: [e-mail]
Cc: [e-mail]
Signed-off-by: Lee Jones <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Acked-by: Palmer Dabbelt <[e-mail]>
Signed-off-by: Stephen Boyd <[e-mail]>

drivers/clk/sifive/fu540-prci.h

···
 
 extern struct __prci_clock __prci_init_clocks_fu540[NUM_CLOCK_FU540];
 
-static const struct prci_clk_desc prci_clk_fu540 = {
-	.clks = __prci_init_clocks_fu540,
-	.num_clks = ARRAY_SIZE(__prci_init_clocks_fu540),
-};
-
 #endif /* __SIFIVE_CLK_FU540_PRCI_H */

drivers/clk/sifive/sifive-prci.c

···
 #include "fu540-prci.h"
 #include "fu740-prci.h"
 
+static const struct prci_clk_desc prci_clk_fu540 = {
+	.clks = __prci_init_clocks_fu540,
+	.num_clks = ARRAY_SIZE(__prci_init_clocks_fu540),
+};
+
 /*
  * Private functions
  */