ci: fix use_make input type in kernel workflows

Change type of use_make input from string to boolean in all kernel build workflows to correctly reflect expected input type

.github/workflows/kernel-a12.yml

@@ -18,7 +18,7 @@ on:
         type: string
       use_make:
         required: true
-        type: string
+        type: boolean
 
 jobs:
   build-kernels-a12:

.github/workflows/kernel-a13.yml

@@ -18,7 +18,7 @@ on:
         type: string
       use_make:
         required: true
-        type: string
+        type: boolean
 
 jobs:
   build-kernels-a13-5-10:

.github/workflows/kernel-a14.yml

@@ -18,7 +18,7 @@ on:
         type: string
       use_make:
         required: true
-        type: string
+        type: boolean
 
 jobs:
   build-kernels-a14-5-15:

.github/workflows/kernel-a15.yml

@@ -18,7 +18,7 @@ on:
         type: string
       use_make:
         required: true
-        type: string
+        type: boolean
 
 jobs:
   build-kernels-a15: