The Debian packaging of uhubctl is maintained in git, using the merging workflow described in dgit-maint-merge(7).  There isn't a patch queue that can be represented as a quilt series.

A detailed breakdown of the changes is available from their canonical representation - git commits in the packaging repository.  For example, to see the changes made by the Debian maintainer in
the first upload of upstream version 1.2.3, you could use:

% git clone https://git.dgit.debian.org/uhubctl
% cd uhubctl
% git log --oneline 1.2.3..debian/1.2.3-1 -- . ':!debian'

(If you have dgit, use `dgit clone uhubctl`, rather than plain `git clone`.)

A single combined diff, containing all the changes, follows.
--- uhubctl-2.3.0.orig/Makefile
+++ uhubctl-2.3.0/Makefile
@@ -14,11 +14,17 @@ RM		:= rm -rf
 CC ?= gcc
 CFLAGS ?= -g -O0
 CFLAGS += -Wall -Wextra -std=c99 -pedantic
+# Gets the full version of the source package including debian version
+DEB_VERSION := $(shell dpkg-parsechangelog | egrep '^Version:' | cut -f 2 -d ' ')
+DEB_NOEPOCH_VERSION := $(shell echo $(DEB_VERSION) | cut -d: -f2-)
+# Gets only the upstream version of the package
+DEB_UPSTREAM_VERSION := $(shell echo $(DEB_NOEPOCH_VERSION) | sed 's/-[^-]*$$//')
+
+CFLAGS += -DPROGRAM_VERSION=\"$(DEB_VERSION)\"
 GIT_VERSION := $(shell git describe --match "v[0-9]*" --abbrev=8 --dirty --tags | cut -c2-)
 ifeq ($(GIT_VERSION),)
 	GIT_VERSION := $(shell cat VERSION)
 endif
-CFLAGS += -DPROGRAM_VERSION=\"$(GIT_VERSION)\"
 
 # Use hardening options on Linux
 ifeq ($(UNAME_S),Linux)
