Create Daisy Petal SM variant

Author: beserge

README.md

@@ -338,6 +338,7 @@ User can add a STM32 based board following this [wiki](https://github.com/stm32d
 | :green_heart: | STM32H750IB<br>STM32H750II | Generic Board | *2.0.0* |  |
 | :green_heart: | STM32H750IB | [Daisy](https://www.electro-smith.com/daisy/daisy) | *1.9.0* |  |
 | :yellow_heart: | STM32H750IB | [Daisy Patch SM](https://www.electro-smith.com/daisy/patch-sm) | *2.2.0* |  |
+| :yellow_heart: | STM32H750IB | [Daisy Petal SM](https://www.electro-smith.com/daisy/petal-125b-sm) | *2.2.0* |  |
 | :green_heart: | STM32H750VB | Generic Board | *2.0.0* |  |
 | :yellow_heart: | STM32H750VB | [DevEBox H750VBT6](https://github.com/mcauser/MCUDEV_DEVEBOX_H7XX_M) | **2.2.0** | |
 | :yellow_heart: | STM32H750VB | [WeAct MiniSTM32H750VBT6](https://github.com/WeActTC/MiniSTM32H7xx) | **2.2.0** | [More info](https://github.com/stm32duino/Arduino_Core_STM32/pull/1552) |

boards.txt

@@ -3748,6 +3748,17 @@ GenH7.menu.pnum.DAISY_PATCH_SM.build.variant=STM32H7xx/H742I(G-I)(K-T)_H743I(G-I
 GenH7.menu.pnum.DAISY_PATCH_SM.build.peripheral_pins=-DCUSTOM_PERIPHERAL_PINS
 GenH7.menu.pnum.DAISY_PATCH_SM.build.ldscript=DAISY_SEED.ld
 
+# Daisy Petal SM board
+GenH7.menu.pnum.DAISY_PETAL_SM=Daisy Petal SM
+GenH7.menu.pnum.DAISY_PETAL_SM.upload.maximum_size=131072
+GenH7.menu.pnum.DAISY_PETAL_SM.upload.maximum_data_size=524288
+GenH7.menu.pnum.DAISY_PETAL_SM.build.board=DAISY_PETAL_SM
+GenH7.menu.pnum.DAISY_PETAL_SM.build.product_line=STM32H750xx
+GenH7.menu.pnum.DAISY_PETAL_SM.build.variant_h=variant_{build.board}.h
+GenH7.menu.pnum.DAISY_PETAL_SM.build.variant=STM32H7xx/H742I(G-I)(K-T)_H743I(G-I)(K-T)_H750IB(K-T)_H753II(K-T)
+GenH7.menu.pnum.DAISY_PETAL_SM.build.peripheral_pins=-DCUSTOM_PERIPHERAL_PINS
+GenH7.menu.pnum.DAISY_PETAL_SM.build.ldscript=DAISY_SEED.ld
+
 # DevEBoxH743VITX
 GenH7.menu.pnum.DevEBoxH743VITX=DevEBox H743VITX
 GenH7.menu.pnum.DevEBoxH743VITX.upload.maximum_size=2097152