system/doc: fix redirection links in docs

Signed-off-by: Ariel Otilibili <[email protected]>

system/doc/reference_manual/modules.md

@@ -164,7 +164,7 @@ is to be preferred since the extra type information can be used by tools to
 produce documentation or find discrepancies.
 
 Read more about behaviours and callback modules in
-[OTP Design Principles](`e:system:spec_proc.md#behaviours`).
+[OTP Design Principles](`e:system:design_principles.md#behaviours`).
 
 ### Record Definitions
 

system/doc/system_principles/system_principles.md

@@ -138,7 +138,7 @@ This requires that the source code is structured as applications
 according to the OTP design principles.
 
 For more information about `.rel` files, see
-[OTP Design Principles](`e:system:release_handling.md`) and the
+[Release Handling](`e:system:release_handling.md`) and the
 [rel](`e:sasl:rel.md`) page in SASL.
 
 To generate the binary boot script file `Name.boot` the boot script file