Add docs for ksymaddr (#118)

Moved docs from gef in hugsy/gef#1141

docs/commands/ksymaddr.md

@@ -0,0 +1,24 @@
+## Command `ksymaddr`
+
+`ksymaddr` helps locate a kernel symbol by its name.
+
+The syntax is straight forward:
+
+```text
+ksymaddr <PATTERN>
+```
+
+For example,
+
+```text
+gef➤  ksymaddr commit_creds
+[+] Found matching symbol for 'commit_creds' at 0xffffffff8f495740 (type=T)
+[*] Found partial match for 'commit_creds' at 0xffffffff8f495740 (type=T): commit_creds
+[*] Found partial match for 'commit_creds' at 0xffffffff8fc71ee0 (type=R): __ksymtab_commit_creds
+[*] Found partial match for 'commit_creds' at 0xffffffff8fc8d008 (type=r): __kcrctab_commit_creds
+[*] Found partial match for 'commit_creds' at 0xffffffff8fc9bfcd (type=r): __kstrtab_commit_creds
+```
+
+Note that the debugging process needs to have the correct permissions for this command to show
+kernel addresses. For more information see also [this stackoverflow
+post](https://stackoverflow.com/a/55592796).

mkdocs.yml

@@ -22,6 +22,7 @@ nav:
   - ftrace: commands/ftrace.md
   - ida-rpyc: commands/ida-rpyc.md
   - is-syscall: commands/is-syscall.md
+  - ksymaddr: commands/ksymaddr.md
   - peekpointers: commands/peekpointers.md
   - retdec: commands/retdec.md
   - ropper: commands/ropper.md