clk: mmp: Adjust checks for NULL pointers

The script “checkpatch.pl” pointed information out like the
following:

	Comparison to NULL could be written !...

Thus fix the affected source code places.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

drivers/clk/mmp/clk-mix.c

@@ -229,7 +229,7 @@ static int mmp_clk_mix_determine_rate(struct clk_hw *hw,
 			parent_rate = clk_hw_get_rate(parent);
 			mix_rate = parent_rate / item->divisor;
 			gap = abs(mix_rate - req->rate);
-			if (parent_best == NULL || gap < gap_best) {
+			if (!parent_best || gap < gap_best) {
 				parent_best = parent;
 				parent_rate_best = parent_rate;
 				mix_rate_best = mix_rate;
@@ -247,7 +247,7 @@ static int mmp_clk_mix_determine_rate(struct clk_hw *hw,
 				div = _get_div(mix, j);
 				mix_rate = parent_rate / div;
 				gap = abs(mix_rate - req->rate);
-				if (parent_best == NULL || gap < gap_best) {
+				if (!parent_best || gap < gap_best) {
 					parent_best = parent;
 					parent_rate_best = parent_rate;
 					mix_rate_best = mix_rate;

drivers/clk/mmp/clk-mmp2.c

@@ -83,19 +83,19 @@ void __init mmp2_clk_init(phys_addr_t mpmu_phys, phys_addr_t apmu_phys,
 	void __iomem *apbc_base;
 
 	mpmu_base = ioremap(mpmu_phys, SZ_4K);
-	if (mpmu_base == NULL) {
+	if (!mpmu_base) {
 		pr_err("error to ioremap MPMU base\n");
 		return;
 	}
 
 	apmu_base = ioremap(apmu_phys, SZ_4K);
-	if (apmu_base == NULL) {
+	if (!apmu_base) {
 		pr_err("error to ioremap APMU base\n");
 		return;
 	}
 
 	apbc_base = ioremap(apbc_phys, SZ_4K);
-	if (apbc_base == NULL) {
+	if (!apbc_base) {
 		pr_err("error to ioremap APBC base\n");
 		return;
 	}

drivers/clk/mmp/clk-pxa168.c

@@ -75,19 +75,19 @@ void __init pxa168_clk_init(phys_addr_t mpmu_phys, phys_addr_t apmu_phys,
 	void __iomem *apbc_base;
 
 	mpmu_base = ioremap(mpmu_phys, SZ_4K);
-	if (mpmu_base == NULL) {
+	if (!mpmu_base) {
 		pr_err("error to ioremap MPMU base\n");
 		return;
 	}
 
 	apmu_base = ioremap(apmu_phys, SZ_4K);
-	if (apmu_base == NULL) {
+	if (!apmu_base) {
 		pr_err("error to ioremap APMU base\n");
 		return;
 	}
 
 	apbc_base = ioremap(apbc_phys, SZ_4K);
-	if (apbc_base == NULL) {
+	if (!apbc_base) {
 		pr_err("error to ioremap APBC base\n");
 		return;
 	}

drivers/clk/mmp/clk-pxa910.c

@@ -74,25 +74,25 @@ void __init pxa910_clk_init(phys_addr_t mpmu_phys, phys_addr_t apmu_phys,
 	void __iomem *apbc_base;
 
 	mpmu_base = ioremap(mpmu_phys, SZ_4K);
-	if (mpmu_base == NULL) {
+	if (!mpmu_base) {
 		pr_err("error to ioremap MPMU base\n");
 		return;
 	}
 
 	apmu_base = ioremap(apmu_phys, SZ_4K);
-	if (apmu_base == NULL) {
+	if (!apmu_base) {
 		pr_err("error to ioremap APMU base\n");
 		return;
 	}
 
 	apbcp_base = ioremap(apbcp_phys, SZ_4K);
-	if (apbcp_base == NULL) {
+	if (!apbcp_base) {
 		pr_err("error to ioremap APBC extension base\n");
 		return;
 	}
 
 	apbc_base = ioremap(apbc_phys, SZ_4K);
-	if (apbc_base == NULL) {
+	if (!apbc_base) {
 		pr_err("error to ioremap APBC base\n");
 		return;
 	}