[PATCH v2] x86/mtrr: Convert to use match_string() helper

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

The helper returns index of the matching string in an array.
Replace the open coded array lookup.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---

- reword commit message

 arch/x86/kernel/cpu/mtrr/if.c | 21 ++++++++++-----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kernel/cpu/mtrr/if.c b/arch/x86/kernel/cpu/mtrr/if.c
index d0fd1a5a098e..3cbae60663fa 100644
--- a/arch/x86/kernel/cpu/mtrr/if.c
+++ b/arch/x86/kernel/cpu/mtrr/if.c
@@ -137,17 +137,16 @@ mtrr_write(struct file *file, const char __user *buf, size_t len, loff_t * ppos)
 		return -EINVAL;
 	ptr = skip_spaces(ptr + 5);
 
-	for (i = 0; i < MTRR_NUM_TYPES; ++i) {
-		if (strcmp(ptr, mtrr_strings[i]))
-			continue;
-		base >>= PAGE_SHIFT;
-		size >>= PAGE_SHIFT;
-		err = mtrr_add_page((unsigned long)base, (unsigned long)size, i, true);
-		if (err < 0)
-			return err;
-		return len;
-	}
-	return -EINVAL;
+	i = match_string(mtrr_strings, MTRR_NUM_TYPES, ptr);
+	if (i < 0)
+		return i;
+
+	base >>= PAGE_SHIFT;
+	size >>= PAGE_SHIFT;
+	err = mtrr_add_page((unsigned long)base, (unsigned long)size, i, true);
+	if (err < 0)
+		return err;
+	return len;
 }
 
 static long
-- 
2.17.0