doc: nrf70: ext_flash: Update instructions

Now that the snippets support sysbuild, no extra SB configs are needed
in the command line.

Signed-off-by: Chaitanya Tata <[email protected]>

Author: krish2718

doc/nrf/app_dev/device_guides/nrf70/fw_patches_ext_flash.rst

@@ -120,14 +120,14 @@ With west
 
 .. code-block:: console
 
-    west build -p -b nrf5340dk/nrf5340/cpuapp samples/wifi/shell -- -Dnrf_wifi_shell_SHIELD=nrf7002ek -Dnrf_wifi_shell_SNIPPET="nrf70-fw-patch-ext-flash" -DSB_CONFIG_WIFI_PATCHES_EXT_FLASH_STORE=y
+    west build -p -b nrf5340dk/nrf5340/cpuapp samples/wifi/shell -- -Dnrf_wifi_shell_SHIELD=nrf7002ek -Dnrf_wifi_shell_SNIPPET="nrf70-fw-patch-ext-flash"
 
 With CMake
 ^^^^^^^^^^
 
 .. code-block:: console
 
-    cmake -GNinja -Bbuild -DBOARD=nrf5340dk/nrf5340/cpuapp -Dnrf_wifi_shell_SHIELD=nrf7002ek -Dnrf_wifi_shell_SNIPPET="nrf70-fw-patch-ext-flash" -DSB_CONFIG_WIFI_PATCHES_EXT_FLASH_STORE=y samples/wifi/shell
+    cmake -GNinja -Bbuild -DBOARD=nrf5340dk/nrf5340/cpuapp -Dnrf_wifi_shell_SHIELD=nrf7002ek -Dnrf_wifi_shell_SNIPPET="nrf70-fw-patch-ext-flash"
     ninja -C build
 
 For example, to build the :ref:`wifi_shell_sample` sample for the nRF5340 DK with partition manager enabled, run the following commands:
@@ -137,14 +137,15 @@ With west
 
 .. code-block:: console
 
-    west build -p -b nrf5340dk/nrf5340/cpuapp samples/wifi/shell -- -Dnrf_wifi_shell_SHIELD=nrf7002ek -DSB_CONFIG_WIFI_PATCHES_EXT_FLASH_STORE=y
+    west build -p -b nrf5340dk/nrf5340/cpuapp samples/wifi/shell -- -Dnrf_wifi_shell_SHIELD=nrf7002ek --snippet=nrf70-fw-patch-ext-flash
 
 With CMake
 ^^^^^^^^^^
 
 .. code-block:: console
 
-    cmake -GNinja -Bbuild -DBOARD=nrf5340dk/nrf5340/cpuapp -Dnrf_wifi_shell_SHIELD=nrf7002ek -DSB_CONFIG_WIFI_PATCHES_EXT_FLASH_STORE=y samples/wifi/shell
+    cmake -GNinja -Bbuild -DBOARD=nrf5340dk/nrf5340/cpuapp -Dnrf_wifi_shell_SHIELD=nrf7002ek --snippet=nrf70-fw-patch-ext-flash
+    samples/wifi/shell
     ninja -C build
 
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