regulator: gpio: Fix the out-of-bounds access to drvdata::gpiods

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: regulator: gpio: Fix the out-of-bounds access to drvdata::gpiods drvdata::gpiods is supposed to hold an array of 'gpio_desc' pointers. But the memory is allocated for only one pointer. This will lead to out-of-bounds access later in the code if 'config::ngpios' is > 1. So fix the code to allocate enough memory to hold 'config::ngpios' of GPIO descriptors. While at it, also move the check for memory allocation failure to be below the allocation to make it more readable.

References

• https://git.kernel.org/stable/c/a3cd5ae7befbac849e0e0529c94ca04e8093cfd2
• https://git.kernel.org/stable/c/9fe71972869faed1f8f9b3beb9040f9c1b300c79
• https://git.kernel.org/stable/c/56738cbac3bbb1d39a71a07f57484dec1db8b239
• https://git.kernel.org/stable/c/a1e12fac214d4f49fcb186dbdf9c5592e7fa0a7a
• https://git.kernel.org/stable/c/24418bc77a66cb5be9f5a837431ba3674ed8b52f
• https://git.kernel.org/stable/c/e4d19e5d71b217940e33f2ef6c6962b7b68c5606
• https://git.kernel.org/stable/c/3830ab97cda9599872625cc0dc7b00160193634f
• https://git.kernel.org/stable/c/c9764fd88bc744592b0604ccb6b6fc1a5f76b4e3