sh: Tidy up pre-clkdev clk_get() error handling.

clk_get() used to return NULL or an errno value depending on whether a
clkdev lookup failed or a clock wasn't found in the primary clock list.
As these disjoint paths were unified and everything now is handled via
clkdev lookups, the NULL case never makes it out of clk_get(). Update
accordingly and always look to the errno value.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/sh/boards/board-apsh4a3a.c

@@ -116,7 +116,7 @@ static int apsh4a3a_clk_init(void)
 	int ret;
 
 	clk = clk_get(NULL, "extal");
-	if (!clk || IS_ERR(clk))
+	if (IS_ERR(clk))
 		return PTR_ERR(clk);
 	ret = clk_set_rate(clk, 33333000);
 	clk_put(clk);

arch/sh/boards/board-apsh4ad0a.c

@@ -94,7 +94,7 @@ static int apsh4ad0a_clk_init(void)
 	int ret;
 
 	clk = clk_get(NULL, "extal");
-	if (!clk || IS_ERR(clk))
+	if (IS_ERR(clk))
 		return PTR_ERR(clk);
 	ret = clk_set_rate(clk, 33333000);
 	clk_put(clk);

arch/sh/boards/board-sh7785lcr.c

@@ -299,7 +299,7 @@ static int sh7785lcr_clk_init(void)
 	int ret;
 
 	clk = clk_get(NULL, "extal");
-	if (!clk || IS_ERR(clk))
+	if (IS_ERR(clk))
 		return PTR_ERR(clk);
 	ret = clk_set_rate(clk, 33333333);
 	clk_put(clk);

arch/sh/boards/board-urquell.c

@@ -190,7 +190,7 @@ static int urquell_clk_init(void)
 		return -EINVAL;
 
 	clk = clk_get(NULL, "extal");
-	if (!clk || IS_ERR(clk))
+	if (IS_ERR(clk))
 		return PTR_ERR(clk);
 	ret = clk_set_rate(clk, 33333333);
 	clk_put(clk);

arch/sh/boards/mach-sdk7786/setup.c

@@ -194,7 +194,7 @@ static int sdk7786_clk_init(void)
 		return -EINVAL;
 
 	clk = clk_get(NULL, "extal");
-	if (!clk || IS_ERR(clk))
+	if (IS_ERR(clk))
 		return PTR_ERR(clk);
 	ret = clk_set_rate(clk, 33333333);
 	clk_put(clk);