doc: update whitespace in release-notes-1.10.rst

Remove gratitious blank lines.

Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
diff --git a/doc/release-notes-1.10.rst b/doc/release-notes-1.10.rst
index 3941e95..52071f5 100644
--- a/doc/release-notes-1.10.rst
+++ b/doc/release-notes-1.10.rst
@@ -35,7 +35,6 @@
   to have those pointers validated; userspace must never be able to crash the
   kernel by passing it garbage.
 
-
 Architectures
 *************
 
@@ -113,8 +112,6 @@
   by include/entropy.h.
 * TinyCrypt updated to version 0.2.8
 
-
-
 HALs
 ****
 
@@ -151,7 +148,6 @@
 * Add userspace protection tests
 * Move all tests to ztest and cleanup coding style and formatting
 
-
 Issue Related Items
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