Merge rust-embedded#352

352: DOC Minor fixes r=eldruin a=NitinSaxenait

### What does this implement/fix?
This is a minor change in the RTRM Section 7.1 which makes it easy to find the BSRR register.
The way we can reach to BSRR register and it's offset value 0x18.

Co-authored-by: Nitin Saxena <[email protected]>
Co-authored-by: Diego Barrios Romero <[email protected]>

Author: 3 people

src/07-registers/rtrm.md

@@ -37,8 +37,9 @@ peripheral, that table is in:
 
 > Section 11.4.12 GPIO register map - Page 243
 
-We are interested in the register that's at an offset of `0x18` from the base address of the `GPIOE`
-peripheral. According to the table, that would be the register `BSRR`.
+'BSRR' is the register which we will be using to set/reset. Its offset value is '0x18' from the base address 
+of the 'GPIOE'. We can look up BSRR in the reference manual. 
+GPIO Registers -> GPIO port bit set/reset register (GPIOx_BSRR).
 
 Now we need to jump to the documentation of that particular register. It's a few pages above in: