Fix MISRA defects in extension libs

No functional changes.

Change-Id: I2f28f20944f552447ac4e9e755493cd7c0ea1192
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
diff --git a/lib/extensions/mpam/mpam.c b/lib/extensions/mpam/mpam.c
index e628827..d57bb47 100644
--- a/lib/extensions/mpam/mpam.c
+++ b/lib/extensions/mpam/mpam.c
@@ -16,7 +16,7 @@
 	return ((features & ID_AA64PFR0_MPAM_MASK) != 0U);
 }
 
-void mpam_enable(int el2_unused)
+void mpam_enable(bool el2_unused)
 {
 	if (!mpam_supported())
 		return;
@@ -31,7 +31,7 @@
 	 * If EL2 is implemented but unused, disable trapping to EL2 when lower
 	 * ELs access their own MPAM registers.
 	 */
-	if (el2_unused != 0) {
+	if (el2_unused) {
 		write_mpam2_el2(0);
 
 		if ((read_mpamidr_el1() & MPAMIDR_HAS_HCR_BIT) != 0U)