Fix Changelog format

Signed-off-by: Janos Follath <janos.follath@arm.com>
diff --git a/ChangeLog.d/bugfix_3782.txt b/ChangeLog.d/bugfix_3782.txt
index 25e18cb..a92dffa 100644
--- a/ChangeLog.d/bugfix_3782.txt
+++ b/ChangeLog.d/bugfix_3782.txt
@@ -1,2 +1,2 @@
 Bugfix
-  * Fix build failures on GCC 11. Fixes #3782.
+   * Fix build failures on GCC 11. Fixes #3782.
diff --git a/ChangeLog.d/clean_pem_buffers.txt b/ChangeLog.d/clean_pem_buffers.txt
index 818fad9..5f79649 100644
--- a/ChangeLog.d/clean_pem_buffers.txt
+++ b/ChangeLog.d/clean_pem_buffers.txt
@@ -1,6 +1,6 @@
 Bugfix
-  * In PEM writing functions, fill the trailing part of the buffer with null
-    bytes. This guarantees that the corresponding parsing function can read
-    the buffer back, which was the case for mbedtls_x509write_{crt,csr}_pem
-    until this property was inadvertently broken in Mbed TLS 2.19.0.
-    Fixes #3682.
+   * In PEM writing functions, fill the trailing part of the buffer with null
+     bytes. This guarantees that the corresponding parsing function can read
+     the buffer back, which was the case for mbedtls_x509write_{crt,csr}_pem
+     until this property was inadvertently broken in Mbed TLS 2.19.0.
+     Fixes #3682.
diff --git a/ChangeLog.d/x509-add-tag-check-to-algorithm-params b/ChangeLog.d/x509-add-tag-check-to-algorithm-params.txt
similarity index 100%
rename from ChangeLog.d/x509-add-tag-check-to-algorithm-params
rename to ChangeLog.d/x509-add-tag-check-to-algorithm-params.txt