git: Add fixes alias and pretty format

This allows printing for 'Fixes:' tags as mentioned in the kernel
documentation:
https://www.kernel.org/doc/html/latest/process/submitting-patches.html

.config/git/config

@@ -3,6 +3,7 @@
 	detachedHead = off
 [alias]
 	branches = track
+	fixes = log -1 --pretty=fixes
 	root = rev-parse --show-toplevel
 	spull = "!__git_spull() { git pull \"$@\" && git submodule sync --recursive && git submodule update --init --recursive; }; __git_spull"
 	track = "!git for-each-ref --format='%(upstream),%(refname)' refs/heads refs/remotes | sort -d | sed -Ez 's:(^|\\n|,)refs/(heads|remotes/):\\1:g; s:(^|\\n),([^/][^\\n]*):\\1\\2,:g; s:,/:,:g; s:(^|\\n)([^,]+),\\n\\2:\\1\\2:g; s:(^|\\n)([^/,]*)([^\\n]*\\n\\2(,|/))*:\\n&:g; s:\\n+$:\\n:' | (echo remote,local; cat) | column -tdLs, -Na,b -Ob,a | sed '2d; 1{p;s/./―/g}'"
@@ -29,6 +30,8 @@
 	log = true
 	suppressDest = *
 	tool = nvimdiff
+[pretty]
+	fixes = Fixes: %h (\"%s\")
 [pull]
 	ff = yes
 	rebase = true